jpayne@69: /* jpayne@69: ** 2001-09-15 jpayne@69: ** jpayne@69: ** The author disclaims copyright to this source code. In place of jpayne@69: ** a legal notice, here is a blessing: jpayne@69: ** jpayne@69: ** May you do good and not evil. jpayne@69: ** May you find forgiveness for yourself and forgive others. jpayne@69: ** May you share freely, never taking more than you give. jpayne@69: ** jpayne@69: ************************************************************************* jpayne@69: ** This header file defines the interface that the SQLite library jpayne@69: ** presents to client programs. If a C-function, structure, datatype, jpayne@69: ** or constant definition does not appear in this file, then it is jpayne@69: ** not a published API of SQLite, is subject to change without jpayne@69: ** notice, and should not be referenced by programs that use SQLite. jpayne@69: ** jpayne@69: ** Some of the definitions that are in this file are marked as jpayne@69: ** "experimental". Experimental interfaces are normally new jpayne@69: ** features recently added to SQLite. We do not anticipate changes jpayne@69: ** to experimental interfaces but reserve the right to make minor changes jpayne@69: ** if experience from use "in the wild" suggest such changes are prudent. jpayne@69: ** jpayne@69: ** The official C-language API documentation for SQLite is derived jpayne@69: ** from comments in this file. This file is the authoritative source jpayne@69: ** on how SQLite interfaces are supposed to operate. jpayne@69: ** jpayne@69: ** The name of this file under configuration management is "sqlite.h.in". jpayne@69: ** The makefile makes some minor changes to this file (such as inserting jpayne@69: ** the version number) and changes its name to "sqlite3.h" as jpayne@69: ** part of the build process. jpayne@69: */ jpayne@69: #ifndef SQLITE3_H jpayne@69: #define SQLITE3_H jpayne@69: #include /* Needed for the definition of va_list */ jpayne@69: jpayne@69: /* jpayne@69: ** Make sure we can call this stuff from C++. jpayne@69: */ jpayne@69: #ifdef __cplusplus jpayne@69: extern "C" { jpayne@69: #endif jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** Facilitate override of interface linkage and calling conventions. jpayne@69: ** Be aware that these macros may not be used within this particular jpayne@69: ** translation of the amalgamation and its associated header file. jpayne@69: ** jpayne@69: ** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the jpayne@69: ** compiler that the target identifier should have external linkage. jpayne@69: ** jpayne@69: ** The SQLITE_CDECL macro is used to set the calling convention for jpayne@69: ** public functions that accept a variable number of arguments. jpayne@69: ** jpayne@69: ** The SQLITE_APICALL macro is used to set the calling convention for jpayne@69: ** public functions that accept a fixed number of arguments. jpayne@69: ** jpayne@69: ** The SQLITE_STDCALL macro is no longer used and is now deprecated. jpayne@69: ** jpayne@69: ** The SQLITE_CALLBACK macro is used to set the calling convention for jpayne@69: ** function pointers. jpayne@69: ** jpayne@69: ** The SQLITE_SYSAPI macro is used to set the calling convention for jpayne@69: ** functions provided by the operating system. jpayne@69: ** jpayne@69: ** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and jpayne@69: ** SQLITE_SYSAPI macros are used only when building for environments jpayne@69: ** that require non-default calling conventions. jpayne@69: */ jpayne@69: #ifndef SQLITE_EXTERN jpayne@69: # define SQLITE_EXTERN extern jpayne@69: #endif jpayne@69: #ifndef SQLITE_API jpayne@69: # define SQLITE_API jpayne@69: #endif jpayne@69: #ifndef SQLITE_CDECL jpayne@69: # define SQLITE_CDECL jpayne@69: #endif jpayne@69: #ifndef SQLITE_APICALL jpayne@69: # define SQLITE_APICALL jpayne@69: #endif jpayne@69: #ifndef SQLITE_STDCALL jpayne@69: # define SQLITE_STDCALL SQLITE_APICALL jpayne@69: #endif jpayne@69: #ifndef SQLITE_CALLBACK jpayne@69: # define SQLITE_CALLBACK jpayne@69: #endif jpayne@69: #ifndef SQLITE_SYSAPI jpayne@69: # define SQLITE_SYSAPI jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** These no-op macros are used in front of interfaces to mark those jpayne@69: ** interfaces as either deprecated or experimental. New applications jpayne@69: ** should not use deprecated interfaces - they are supported for backwards jpayne@69: ** compatibility only. Application writers should be aware that jpayne@69: ** experimental interfaces are subject to change in point releases. jpayne@69: ** jpayne@69: ** These macros used to resolve to various kinds of compiler magic that jpayne@69: ** would generate warning messages when they were used. But that jpayne@69: ** compiler magic ended up generating such a flurry of bug reports jpayne@69: ** that we have taken it all out and gone back to using simple jpayne@69: ** noop macros. jpayne@69: */ jpayne@69: #define SQLITE_DEPRECATED jpayne@69: #define SQLITE_EXPERIMENTAL jpayne@69: jpayne@69: /* jpayne@69: ** Ensure these symbols were not defined by some previous header file. jpayne@69: */ jpayne@69: #ifdef SQLITE_VERSION jpayne@69: # undef SQLITE_VERSION jpayne@69: #endif jpayne@69: #ifdef SQLITE_VERSION_NUMBER jpayne@69: # undef SQLITE_VERSION_NUMBER jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Compile-Time Library Version Numbers jpayne@69: ** jpayne@69: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header jpayne@69: ** evaluates to a string literal that is the SQLite version in the jpayne@69: ** format "X.Y.Z" where X is the major version number (always 3 for jpayne@69: ** SQLite3) and Y is the minor version number and Z is the release number.)^ jpayne@69: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer jpayne@69: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same jpayne@69: ** numbers used in [SQLITE_VERSION].)^ jpayne@69: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also jpayne@69: ** be larger than the release from which it is derived. Either Y will jpayne@69: ** be held constant and Z will be incremented or else Y will be incremented jpayne@69: ** and Z will be reset to zero. jpayne@69: ** jpayne@69: ** Since [version 3.6.18] ([dateof:3.6.18]), jpayne@69: ** SQLite source code has been stored in the jpayne@69: ** Fossil configuration management jpayne@69: ** system. ^The SQLITE_SOURCE_ID macro evaluates to jpayne@69: ** a string which identifies a particular check-in of SQLite jpayne@69: ** within its configuration management system. ^The SQLITE_SOURCE_ID jpayne@69: ** string contains the date and time of the check-in (UTC) and a SHA1 jpayne@69: ** or SHA3-256 hash of the entire source tree. If the source code has jpayne@69: ** been edited in any way since it was last checked in, then the last jpayne@69: ** four hexadecimal digits of the hash may be modified. jpayne@69: ** jpayne@69: ** See also: [sqlite3_libversion()], jpayne@69: ** [sqlite3_libversion_number()], [sqlite3_sourceid()], jpayne@69: ** [sqlite_version()] and [sqlite_source_id()]. jpayne@69: */ jpayne@69: #define SQLITE_VERSION "3.46.0" jpayne@69: #define SQLITE_VERSION_NUMBER 3046000 jpayne@69: #define SQLITE_SOURCE_ID "2024-05-23 13:25:27 96c92aba00c8375bc32fafcdf12429c58bd8aabfcadab6683e35bbb9cdebf19e" jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Run-Time Library Version Numbers jpayne@69: ** KEYWORDS: sqlite3_version sqlite3_sourceid jpayne@69: ** jpayne@69: ** These interfaces provide the same information as the [SQLITE_VERSION], jpayne@69: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros jpayne@69: ** but are associated with the library instead of the header file. ^(Cautious jpayne@69: ** programmers might include assert() statements in their application to jpayne@69: ** verify that values returned by these interfaces match the macros in jpayne@69: ** the header, and thus ensure that the application is jpayne@69: ** compiled with matching library and header files. jpayne@69: ** jpayne@69: ** 
jpayne@69: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
jpayne@69: ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
jpayne@69: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] jpayne@69: ** macro. ^The sqlite3_libversion() function returns a pointer to the jpayne@69: ** to the sqlite3_version[] string constant. The sqlite3_libversion() jpayne@69: ** function is provided for use in DLLs since DLL users usually do not have jpayne@69: ** direct access to string constants within the DLL. ^The jpayne@69: ** sqlite3_libversion_number() function returns an integer equal to jpayne@69: ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns jpayne@69: ** a pointer to a string constant whose value is the same as the jpayne@69: ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built jpayne@69: ** using an edited copy of [the amalgamation], then the last four characters jpayne@69: ** of the hash might be different from [SQLITE_SOURCE_ID].)^ jpayne@69: ** jpayne@69: ** See also: [sqlite_version()] and [sqlite_source_id()]. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; jpayne@69: SQLITE_API const char *sqlite3_libversion(void); jpayne@69: SQLITE_API const char *sqlite3_sourceid(void); jpayne@69: SQLITE_API int sqlite3_libversion_number(void); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics jpayne@69: ** jpayne@69: ** ^The sqlite3_compileoption_used() function returns 0 or 1 jpayne@69: ** indicating whether the specified option was defined at jpayne@69: ** compile time. ^The SQLITE_ prefix may be omitted from the jpayne@69: ** option name passed to sqlite3_compileoption_used(). jpayne@69: ** jpayne@69: ** ^The sqlite3_compileoption_get() function allows iterating jpayne@69: ** over the list of options that were defined at compile time by jpayne@69: ** returning the N-th compile time option string. ^If N is out of range, jpayne@69: ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ jpayne@69: ** prefix is omitted from any strings returned by jpayne@69: ** sqlite3_compileoption_get(). jpayne@69: ** jpayne@69: ** ^Support for the diagnostic functions sqlite3_compileoption_used() jpayne@69: ** and sqlite3_compileoption_get() may be omitted by specifying the jpayne@69: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. jpayne@69: ** jpayne@69: ** See also: SQL functions [sqlite_compileoption_used()] and jpayne@69: ** [sqlite_compileoption_get()] and the [compile_options pragma]. jpayne@69: */ jpayne@69: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS jpayne@69: SQLITE_API int sqlite3_compileoption_used(const char *zOptName); jpayne@69: SQLITE_API const char *sqlite3_compileoption_get(int N); jpayne@69: #else jpayne@69: # define sqlite3_compileoption_used(X) 0 jpayne@69: # define sqlite3_compileoption_get(X) ((void*)0) jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Test To See If The Library Is Threadsafe jpayne@69: ** jpayne@69: ** ^The sqlite3_threadsafe() function returns zero if and only if jpayne@69: ** SQLite was compiled with mutexing code omitted due to the jpayne@69: ** [SQLITE_THREADSAFE] compile-time option being set to 0. jpayne@69: ** jpayne@69: ** SQLite can be compiled with or without mutexes. When jpayne@69: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes jpayne@69: ** are enabled and SQLite is threadsafe. When the jpayne@69: ** [SQLITE_THREADSAFE] macro is 0, jpayne@69: ** the mutexes are omitted. Without the mutexes, it is not safe jpayne@69: ** to use SQLite concurrently from more than one thread. jpayne@69: ** jpayne@69: ** Enabling mutexes incurs a measurable performance penalty. jpayne@69: ** So if speed is of utmost importance, it makes sense to disable jpayne@69: ** the mutexes. But for maximum safety, mutexes should be enabled. jpayne@69: ** ^The default behavior is for mutexes to be enabled. jpayne@69: ** jpayne@69: ** This interface can be used by an application to make sure that the jpayne@69: ** version of SQLite that it is linking against was compiled with jpayne@69: ** the desired setting of the [SQLITE_THREADSAFE] macro. jpayne@69: ** jpayne@69: ** This interface only reports on the compile-time mutex setting jpayne@69: ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with jpayne@69: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but jpayne@69: ** can be fully or partially disabled using a call to [sqlite3_config()] jpayne@69: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], jpayne@69: ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the jpayne@69: ** sqlite3_threadsafe() function shows only the compile-time setting of jpayne@69: ** thread safety, not any run-time changes to that setting made by jpayne@69: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() jpayne@69: ** is unchanged by calls to sqlite3_config().)^ jpayne@69: ** jpayne@69: ** See the [threading mode] documentation for additional information. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_threadsafe(void); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Connection Handle jpayne@69: ** KEYWORDS: {database connection} {database connections} jpayne@69: ** jpayne@69: ** Each open SQLite database is represented by a pointer to an instance of jpayne@69: ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 jpayne@69: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and jpayne@69: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] jpayne@69: ** and [sqlite3_close_v2()] are its destructors. There are many other jpayne@69: ** interfaces (such as jpayne@69: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and jpayne@69: ** [sqlite3_busy_timeout()] to name but three) that are methods on an jpayne@69: ** sqlite3 object. jpayne@69: */ jpayne@69: typedef struct sqlite3 sqlite3; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: 64-Bit Integer Types jpayne@69: ** KEYWORDS: sqlite_int64 sqlite_uint64 jpayne@69: ** jpayne@69: ** Because there is no cross-platform way to specify 64-bit integer types jpayne@69: ** SQLite includes typedefs for 64-bit signed and unsigned integers. jpayne@69: ** jpayne@69: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. jpayne@69: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards jpayne@69: ** compatibility only. jpayne@69: ** jpayne@69: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values jpayne@69: ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The jpayne@69: ** sqlite3_uint64 and sqlite_uint64 types can store integer values jpayne@69: ** between 0 and +18446744073709551615 inclusive. jpayne@69: */ jpayne@69: #ifdef SQLITE_INT64_TYPE jpayne@69: typedef SQLITE_INT64_TYPE sqlite_int64; jpayne@69: # ifdef SQLITE_UINT64_TYPE jpayne@69: typedef SQLITE_UINT64_TYPE sqlite_uint64; jpayne@69: # else jpayne@69: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; jpayne@69: # endif jpayne@69: #elif defined(_MSC_VER) || defined(__BORLANDC__) jpayne@69: typedef __int64 sqlite_int64; jpayne@69: typedef unsigned __int64 sqlite_uint64; jpayne@69: #else jpayne@69: typedef long long int sqlite_int64; jpayne@69: typedef unsigned long long int sqlite_uint64; jpayne@69: #endif jpayne@69: typedef sqlite_int64 sqlite3_int64; jpayne@69: typedef sqlite_uint64 sqlite3_uint64; jpayne@69: jpayne@69: /* jpayne@69: ** If compiling for a processor that lacks floating point support, jpayne@69: ** substitute integer for floating-point. jpayne@69: */ jpayne@69: #ifdef SQLITE_OMIT_FLOATING_POINT jpayne@69: # define double sqlite3_int64 jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Closing A Database Connection jpayne@69: ** DESTRUCTOR: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors jpayne@69: ** for the [sqlite3] object. jpayne@69: ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if jpayne@69: ** the [sqlite3] object is successfully destroyed and all associated jpayne@69: ** resources are deallocated. jpayne@69: ** jpayne@69: ** Ideally, applications should [sqlite3_finalize | finalize] all jpayne@69: ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and jpayne@69: ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated jpayne@69: ** with the [sqlite3] object prior to attempting to close the object. jpayne@69: ** ^If the database connection is associated with unfinalized prepared jpayne@69: ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then jpayne@69: ** sqlite3_close() will leave the database connection open and return jpayne@69: ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared jpayne@69: ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, jpayne@69: ** it returns [SQLITE_OK] regardless, but instead of deallocating the database jpayne@69: ** connection immediately, it marks the database connection as an unusable jpayne@69: ** "zombie" and makes arrangements to automatically deallocate the database jpayne@69: ** connection after all prepared statements are finalized, all BLOB handles jpayne@69: ** are closed, and all backups have finished. The sqlite3_close_v2() interface jpayne@69: ** is intended for use with host languages that are garbage collected, and jpayne@69: ** where the order in which destructors are called is arbitrary. jpayne@69: ** jpayne@69: ** ^If an [sqlite3] object is destroyed while a transaction is open, jpayne@69: ** the transaction is automatically rolled back. jpayne@69: ** jpayne@69: ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] jpayne@69: ** must be either a NULL jpayne@69: ** pointer or an [sqlite3] object pointer obtained jpayne@69: ** from [sqlite3_open()], [sqlite3_open16()], or jpayne@69: ** [sqlite3_open_v2()], and not previously closed. jpayne@69: ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer jpayne@69: ** argument is a harmless no-op. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_close(sqlite3*); jpayne@69: SQLITE_API int sqlite3_close_v2(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** The type for a callback function. jpayne@69: ** This is legacy and deprecated. It is included for historical jpayne@69: ** compatibility and is not documented. jpayne@69: */ jpayne@69: typedef int (*sqlite3_callback)(void*,int,char**, char**); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: One-Step Query Execution Interface jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** The sqlite3_exec() interface is a convenience wrapper around jpayne@69: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], jpayne@69: ** that allows an application to run multiple statements of SQL jpayne@69: ** without having to use a lot of C code. jpayne@69: ** jpayne@69: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, jpayne@69: ** semicolon-separate SQL statements passed into its 2nd argument, jpayne@69: ** in the context of the [database connection] passed in as its 1st jpayne@69: ** argument. ^If the callback function of the 3rd argument to jpayne@69: ** sqlite3_exec() is not NULL, then it is invoked for each result row jpayne@69: ** coming out of the evaluated SQL statements. ^The 4th argument to jpayne@69: ** sqlite3_exec() is relayed through to the 1st argument of each jpayne@69: ** callback invocation. ^If the callback pointer to sqlite3_exec() jpayne@69: ** is NULL, then no callback is ever invoked and result rows are jpayne@69: ** ignored. jpayne@69: ** jpayne@69: ** ^If an error occurs while evaluating the SQL statements passed into jpayne@69: ** sqlite3_exec(), then execution of the current statement stops and jpayne@69: ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() jpayne@69: ** is not NULL then any error message is written into memory obtained jpayne@69: ** from [sqlite3_malloc()] and passed back through the 5th parameter. jpayne@69: ** To avoid memory leaks, the application should invoke [sqlite3_free()] jpayne@69: ** on error message strings returned through the 5th parameter of jpayne@69: ** sqlite3_exec() after the error message string is no longer needed. jpayne@69: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors jpayne@69: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to jpayne@69: ** NULL before returning. jpayne@69: ** jpayne@69: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() jpayne@69: ** routine returns SQLITE_ABORT without invoking the callback again and jpayne@69: ** without running any subsequent SQL statements. jpayne@69: ** jpayne@69: ** ^The 2nd argument to the sqlite3_exec() callback function is the jpayne@69: ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() jpayne@69: ** callback is an array of pointers to strings obtained as if from jpayne@69: ** [sqlite3_column_text()], one for each column. ^If an element of a jpayne@69: ** result row is NULL then the corresponding string pointer for the jpayne@69: ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the jpayne@69: ** sqlite3_exec() callback is an array of pointers to strings where each jpayne@69: ** entry represents the name of corresponding result column as obtained jpayne@69: ** from [sqlite3_column_name()]. jpayne@69: ** jpayne@69: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer jpayne@69: ** to an empty string, or a pointer that contains only whitespace and/or jpayne@69: ** SQL comments, then no SQL statements are evaluated and the database jpayne@69: ** is not changed. jpayne@69: ** jpayne@69: ** Restrictions: jpayne@69: ** jpayne@69: ** jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_exec( jpayne@69: sqlite3*, /* An open database */ jpayne@69: const char *sql, /* SQL to be evaluated */ jpayne@69: int (*callback)(void*,int,char**,char**), /* Callback function */ jpayne@69: void *, /* 1st argument to callback */ jpayne@69: char **errmsg /* Error msg written here */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Result Codes jpayne@69: ** KEYWORDS: {result code definitions} jpayne@69: ** jpayne@69: ** Many SQLite functions return an integer result code from the set shown jpayne@69: ** here in order to indicate success or failure. jpayne@69: ** jpayne@69: ** New error codes may be added in future versions of SQLite. jpayne@69: ** jpayne@69: ** See also: [extended result code definitions] jpayne@69: */ jpayne@69: #define SQLITE_OK 0 /* Successful result */ jpayne@69: /* beginning-of-error-codes */ jpayne@69: #define SQLITE_ERROR 1 /* Generic error */ jpayne@69: #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ jpayne@69: #define SQLITE_PERM 3 /* Access permission denied */ jpayne@69: #define SQLITE_ABORT 4 /* Callback routine requested an abort */ jpayne@69: #define SQLITE_BUSY 5 /* The database file is locked */ jpayne@69: #define SQLITE_LOCKED 6 /* A table in the database is locked */ jpayne@69: #define SQLITE_NOMEM 7 /* A malloc() failed */ jpayne@69: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ jpayne@69: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ jpayne@69: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ jpayne@69: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ jpayne@69: #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ jpayne@69: #define SQLITE_FULL 13 /* Insertion failed because database is full */ jpayne@69: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ jpayne@69: #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ jpayne@69: #define SQLITE_EMPTY 16 /* Internal use only */ jpayne@69: #define SQLITE_SCHEMA 17 /* The database schema changed */ jpayne@69: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ jpayne@69: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ jpayne@69: #define SQLITE_MISMATCH 20 /* Data type mismatch */ jpayne@69: #define SQLITE_MISUSE 21 /* Library used incorrectly */ jpayne@69: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ jpayne@69: #define SQLITE_AUTH 23 /* Authorization denied */ jpayne@69: #define SQLITE_FORMAT 24 /* Not used */ jpayne@69: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ jpayne@69: #define SQLITE_NOTADB 26 /* File opened that is not a database file */ jpayne@69: #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ jpayne@69: #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ jpayne@69: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ jpayne@69: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ jpayne@69: /* end-of-error-codes */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Extended Result Codes jpayne@69: ** KEYWORDS: {extended result code definitions} jpayne@69: ** jpayne@69: ** In its default configuration, SQLite API routines return one of 30 integer jpayne@69: ** [result codes]. However, experience has shown that many of jpayne@69: ** these result codes are too coarse-grained. They do not provide as jpayne@69: ** much information about problems as programmers might like. In an effort to jpayne@69: ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] jpayne@69: ** and later) include jpayne@69: ** support for additional result codes that provide more detailed information jpayne@69: ** about errors. These [extended result codes] are enabled or disabled jpayne@69: ** on a per database connection basis using the jpayne@69: ** [sqlite3_extended_result_codes()] API. Or, the extended code for jpayne@69: ** the most recent error can be obtained using jpayne@69: ** [sqlite3_extended_errcode()]. jpayne@69: */ jpayne@69: #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) jpayne@69: #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) jpayne@69: #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) jpayne@69: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) jpayne@69: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) jpayne@69: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) jpayne@69: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) jpayne@69: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) jpayne@69: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) jpayne@69: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) jpayne@69: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) jpayne@69: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) jpayne@69: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) jpayne@69: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) jpayne@69: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) jpayne@69: #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) jpayne@69: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) jpayne@69: #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) jpayne@69: #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) jpayne@69: #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) jpayne@69: #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) jpayne@69: #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) jpayne@69: #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) jpayne@69: #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) jpayne@69: #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) jpayne@69: #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) jpayne@69: #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) jpayne@69: #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) jpayne@69: #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) jpayne@69: #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) jpayne@69: #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) jpayne@69: #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) jpayne@69: #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) jpayne@69: #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) jpayne@69: #define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) jpayne@69: #define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) jpayne@69: #define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8)) jpayne@69: #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) jpayne@69: #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) jpayne@69: #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) jpayne@69: #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) jpayne@69: #define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) jpayne@69: #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) jpayne@69: #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) jpayne@69: #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) jpayne@69: #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) jpayne@69: #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ jpayne@69: #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) jpayne@69: #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) jpayne@69: #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) jpayne@69: #define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) jpayne@69: #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) jpayne@69: #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) jpayne@69: #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) jpayne@69: #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) jpayne@69: #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) jpayne@69: #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) jpayne@69: #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) jpayne@69: #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) jpayne@69: #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) jpayne@69: #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) jpayne@69: #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) jpayne@69: #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) jpayne@69: #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) jpayne@69: #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) jpayne@69: #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) jpayne@69: #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) jpayne@69: #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) jpayne@69: #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) jpayne@69: #define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) jpayne@69: #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) jpayne@69: #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) jpayne@69: #define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8)) jpayne@69: #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) jpayne@69: #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) jpayne@69: #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) jpayne@69: #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags For File Open Operations jpayne@69: ** jpayne@69: ** These bit values are intended for use in the jpayne@69: ** 3rd parameter to the [sqlite3_open_v2()] interface and jpayne@69: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. jpayne@69: ** jpayne@69: ** Only those flags marked as "Ok for sqlite3_open_v2()" may be jpayne@69: ** used as the third argument to the [sqlite3_open_v2()] interface. jpayne@69: ** The other flags have historically been ignored by sqlite3_open_v2(), jpayne@69: ** though future versions of SQLite might change so that an error is jpayne@69: ** raised if any of the disallowed bits are passed into sqlite3_open_v2(). jpayne@69: ** Applications should not depend on the historical behavior. jpayne@69: ** jpayne@69: ** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into jpayne@69: ** [sqlite3_open_v2()] does *not* cause the underlying database file jpayne@69: ** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into jpayne@69: ** [sqlite3_open_v2()] has historically be a no-op and might become an jpayne@69: ** error in future versions of SQLite. jpayne@69: */ jpayne@69: #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ jpayne@69: #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ jpayne@69: #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ jpayne@69: #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ jpayne@69: #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ jpayne@69: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ jpayne@69: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ jpayne@69: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ jpayne@69: #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ jpayne@69: #define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ jpayne@69: #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ jpayne@69: #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ jpayne@69: #define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ jpayne@69: jpayne@69: /* Reserved: 0x00F00000 */ jpayne@69: /* Legacy compatibility: */ jpayne@69: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Device Characteristics jpayne@69: ** jpayne@69: ** The xDeviceCharacteristics method of the [sqlite3_io_methods] jpayne@69: ** object returns an integer which is a vector of these jpayne@69: ** bit values expressing I/O characteristics of the mass storage jpayne@69: ** device that holds the file that the [sqlite3_io_methods] jpayne@69: ** refers to. jpayne@69: ** jpayne@69: ** The SQLITE_IOCAP_ATOMIC property means that all writes of jpayne@69: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values jpayne@69: ** mean that writes of blocks that are nnn bytes in size and jpayne@69: ** are aligned to an address which is an integer multiple of jpayne@69: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means jpayne@69: ** that when data is appended to a file, the data is appended jpayne@69: ** first then the size of the file is extended, never the other jpayne@69: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that jpayne@69: ** information is written to disk in the same order as calls jpayne@69: ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that jpayne@69: ** after reboot following a crash or power loss, the only bytes in a jpayne@69: ** file that were written at the application level might have changed jpayne@69: ** and that adjacent bytes, even bytes within the same sector are jpayne@69: ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN jpayne@69: ** flag indicates that a file cannot be deleted when open. The jpayne@69: ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on jpayne@69: ** read-only media and cannot be changed even by processes with jpayne@69: ** elevated privileges. jpayne@69: ** jpayne@69: ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying jpayne@69: ** filesystem supports doing multiple write operations atomically when those jpayne@69: ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and jpayne@69: ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. jpayne@69: */ jpayne@69: #define SQLITE_IOCAP_ATOMIC 0x00000001 jpayne@69: #define SQLITE_IOCAP_ATOMIC512 0x00000002 jpayne@69: #define SQLITE_IOCAP_ATOMIC1K 0x00000004 jpayne@69: #define SQLITE_IOCAP_ATOMIC2K 0x00000008 jpayne@69: #define SQLITE_IOCAP_ATOMIC4K 0x00000010 jpayne@69: #define SQLITE_IOCAP_ATOMIC8K 0x00000020 jpayne@69: #define SQLITE_IOCAP_ATOMIC16K 0x00000040 jpayne@69: #define SQLITE_IOCAP_ATOMIC32K 0x00000080 jpayne@69: #define SQLITE_IOCAP_ATOMIC64K 0x00000100 jpayne@69: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 jpayne@69: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 jpayne@69: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 jpayne@69: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 jpayne@69: #define SQLITE_IOCAP_IMMUTABLE 0x00002000 jpayne@69: #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: File Locking Levels jpayne@69: ** jpayne@69: ** SQLite uses one of these integer values as the second jpayne@69: ** argument to calls it makes to the xLock() and xUnlock() methods jpayne@69: ** of an [sqlite3_io_methods] object. These values are ordered from jpayne@69: ** lest restrictive to most restrictive. jpayne@69: ** jpayne@69: ** The argument to xLock() is always SHARED or higher. The argument to jpayne@69: ** xUnlock is either SHARED or NONE. jpayne@69: */ jpayne@69: #define SQLITE_LOCK_NONE 0 /* xUnlock() only */ jpayne@69: #define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ jpayne@69: #define SQLITE_LOCK_RESERVED 2 /* xLock() only */ jpayne@69: #define SQLITE_LOCK_PENDING 3 /* xLock() only */ jpayne@69: #define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Synchronization Type Flags jpayne@69: ** jpayne@69: ** When SQLite invokes the xSync() method of an jpayne@69: ** [sqlite3_io_methods] object it uses a combination of jpayne@69: ** these integer values as the second argument. jpayne@69: ** jpayne@69: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the jpayne@69: ** sync operation only needs to flush data to mass storage. Inode jpayne@69: ** information need not be flushed. If the lower four bits of the flag jpayne@69: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. jpayne@69: ** If the lower four bits equal SQLITE_SYNC_FULL, that means jpayne@69: ** to use Mac OS X style fullsync instead of fsync(). jpayne@69: ** jpayne@69: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags jpayne@69: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL jpayne@69: ** settings. The [synchronous pragma] determines when calls to the jpayne@69: ** xSync VFS method occur and applies uniformly across all platforms. jpayne@69: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how jpayne@69: ** energetic or rigorous or forceful the sync operations are and jpayne@69: ** only make a difference on Mac OSX for the default SQLite code. jpayne@69: ** (Third-party VFS implementations might also make the distinction jpayne@69: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the jpayne@69: ** operating systems natively supported by SQLite, only Mac OSX jpayne@69: ** cares about the difference.) jpayne@69: */ jpayne@69: #define SQLITE_SYNC_NORMAL 0x00002 jpayne@69: #define SQLITE_SYNC_FULL 0x00003 jpayne@69: #define SQLITE_SYNC_DATAONLY 0x00010 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: OS Interface Open File Handle jpayne@69: ** jpayne@69: ** An [sqlite3_file] object represents an open file in the jpayne@69: ** [sqlite3_vfs | OS interface layer]. Individual OS interface jpayne@69: ** implementations will jpayne@69: ** want to subclass this object by appending additional fields jpayne@69: ** for their own use. The pMethods entry is a pointer to an jpayne@69: ** [sqlite3_io_methods] object that defines methods for performing jpayne@69: ** I/O operations on the open file. jpayne@69: */ jpayne@69: typedef struct sqlite3_file sqlite3_file; jpayne@69: struct sqlite3_file { jpayne@69: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: OS Interface File Virtual Methods Object jpayne@69: ** jpayne@69: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an jpayne@69: ** [sqlite3_file] object (or, more commonly, a subclass of the jpayne@69: ** [sqlite3_file] object) with a pointer to an instance of this object. jpayne@69: ** This object defines the methods used to perform various operations jpayne@69: ** against the open file represented by the [sqlite3_file] object. jpayne@69: ** jpayne@69: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element jpayne@69: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method jpayne@69: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The jpayne@69: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] jpayne@69: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element jpayne@69: ** to NULL. jpayne@69: ** jpayne@69: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or jpayne@69: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). jpayne@69: ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] jpayne@69: ** flag may be ORed in to indicate that only the data of the file jpayne@69: ** and not its inode needs to be synced. jpayne@69: ** jpayne@69: ** The integer values to xLock() and xUnlock() are one of jpayne@69: ** jpayne@69: ** xLock() upgrades the database file lock. In other words, xLock() moves the jpayne@69: ** database file lock in the direction NONE toward EXCLUSIVE. The argument to jpayne@69: ** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never jpayne@69: ** SQLITE_LOCK_NONE. If the database file lock is already at or above the jpayne@69: ** requested lock, then the call to xLock() is a no-op. jpayne@69: ** xUnlock() downgrades the database file lock to either SHARED or NONE. jpayne@69: ** If the lock is already at or below the requested lock state, then the call jpayne@69: ** to xUnlock() is a no-op. jpayne@69: ** The xCheckReservedLock() method checks whether any database connection, jpayne@69: ** either in this process or in some other process, is holding a RESERVED, jpayne@69: ** PENDING, or EXCLUSIVE lock on the file. It returns true jpayne@69: ** if such a lock exists and false otherwise. jpayne@69: ** jpayne@69: ** The xFileControl() method is a generic interface that allows custom jpayne@69: ** VFS implementations to directly control an open file using the jpayne@69: ** [sqlite3_file_control()] interface. The second "op" argument is an jpayne@69: ** integer opcode. The third argument is a generic pointer intended to jpayne@69: ** point to a structure that may contain arguments or space in which to jpayne@69: ** write return values. Potential uses for xFileControl() might be jpayne@69: ** functions to enable blocking locks with timeouts, to change the jpayne@69: ** locking strategy (for example to use dot-file locks), to inquire jpayne@69: ** about the status of a lock, or to break stale locks. The SQLite jpayne@69: ** core reserves all opcodes less than 100 for its own use. jpayne@69: ** A [file control opcodes | list of opcodes] less than 100 is available. jpayne@69: ** Applications that define a custom xFileControl method should use opcodes jpayne@69: ** greater than 100 to avoid conflicts. VFS implementations should jpayne@69: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not jpayne@69: ** recognize. jpayne@69: ** jpayne@69: ** The xSectorSize() method returns the sector size of the jpayne@69: ** device that underlies the file. The sector size is the jpayne@69: ** minimum write that can be performed without disturbing jpayne@69: ** other bytes in the file. The xDeviceCharacteristics() jpayne@69: ** method returns a bit vector describing behaviors of the jpayne@69: ** underlying device: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** The SQLITE_IOCAP_ATOMIC property means that all writes of jpayne@69: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values jpayne@69: ** mean that writes of blocks that are nnn bytes in size and jpayne@69: ** are aligned to an address which is an integer multiple of jpayne@69: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means jpayne@69: ** that when data is appended to a file, the data is appended jpayne@69: ** first then the size of the file is extended, never the other jpayne@69: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that jpayne@69: ** information is written to disk in the same order as calls jpayne@69: ** to xWrite(). jpayne@69: ** jpayne@69: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill jpayne@69: ** in the unread portions of the buffer with zeros. A VFS that jpayne@69: ** fails to zero-fill short reads might seem to work. However, jpayne@69: ** failure to zero-fill short reads will eventually lead to jpayne@69: ** database corruption. jpayne@69: */ jpayne@69: typedef struct sqlite3_io_methods sqlite3_io_methods; jpayne@69: struct sqlite3_io_methods { jpayne@69: int iVersion; jpayne@69: int (*xClose)(sqlite3_file*); jpayne@69: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); jpayne@69: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); jpayne@69: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); jpayne@69: int (*xSync)(sqlite3_file*, int flags); jpayne@69: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); jpayne@69: int (*xLock)(sqlite3_file*, int); jpayne@69: int (*xUnlock)(sqlite3_file*, int); jpayne@69: int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); jpayne@69: int (*xFileControl)(sqlite3_file*, int op, void *pArg); jpayne@69: int (*xSectorSize)(sqlite3_file*); jpayne@69: int (*xDeviceCharacteristics)(sqlite3_file*); jpayne@69: /* Methods above are valid for version 1 */ jpayne@69: int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); jpayne@69: int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); jpayne@69: void (*xShmBarrier)(sqlite3_file*); jpayne@69: int (*xShmUnmap)(sqlite3_file*, int deleteFlag); jpayne@69: /* Methods above are valid for version 2 */ jpayne@69: int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); jpayne@69: int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); jpayne@69: /* Methods above are valid for version 3 */ jpayne@69: /* Additional methods may be added in future releases */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Standard File Control Opcodes jpayne@69: ** KEYWORDS: {file control opcodes} {file control opcode} jpayne@69: ** jpayne@69: ** These integer constants are opcodes for the xFileControl method jpayne@69: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] jpayne@69: ** interface. jpayne@69: ** jpayne@69: ** jpayne@69: */ jpayne@69: #define SQLITE_FCNTL_LOCKSTATE 1 jpayne@69: #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 jpayne@69: #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 jpayne@69: #define SQLITE_FCNTL_LAST_ERRNO 4 jpayne@69: #define SQLITE_FCNTL_SIZE_HINT 5 jpayne@69: #define SQLITE_FCNTL_CHUNK_SIZE 6 jpayne@69: #define SQLITE_FCNTL_FILE_POINTER 7 jpayne@69: #define SQLITE_FCNTL_SYNC_OMITTED 8 jpayne@69: #define SQLITE_FCNTL_WIN32_AV_RETRY 9 jpayne@69: #define SQLITE_FCNTL_PERSIST_WAL 10 jpayne@69: #define SQLITE_FCNTL_OVERWRITE 11 jpayne@69: #define SQLITE_FCNTL_VFSNAME 12 jpayne@69: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 jpayne@69: #define SQLITE_FCNTL_PRAGMA 14 jpayne@69: #define SQLITE_FCNTL_BUSYHANDLER 15 jpayne@69: #define SQLITE_FCNTL_TEMPFILENAME 16 jpayne@69: #define SQLITE_FCNTL_MMAP_SIZE 18 jpayne@69: #define SQLITE_FCNTL_TRACE 19 jpayne@69: #define SQLITE_FCNTL_HAS_MOVED 20 jpayne@69: #define SQLITE_FCNTL_SYNC 21 jpayne@69: #define SQLITE_FCNTL_COMMIT_PHASETWO 22 jpayne@69: #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 jpayne@69: #define SQLITE_FCNTL_WAL_BLOCK 24 jpayne@69: #define SQLITE_FCNTL_ZIPVFS 25 jpayne@69: #define SQLITE_FCNTL_RBU 26 jpayne@69: #define SQLITE_FCNTL_VFS_POINTER 27 jpayne@69: #define SQLITE_FCNTL_JOURNAL_POINTER 28 jpayne@69: #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 jpayne@69: #define SQLITE_FCNTL_PDB 30 jpayne@69: #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 jpayne@69: #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 jpayne@69: #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 jpayne@69: #define SQLITE_FCNTL_LOCK_TIMEOUT 34 jpayne@69: #define SQLITE_FCNTL_DATA_VERSION 35 jpayne@69: #define SQLITE_FCNTL_SIZE_LIMIT 36 jpayne@69: #define SQLITE_FCNTL_CKPT_DONE 37 jpayne@69: #define SQLITE_FCNTL_RESERVE_BYTES 38 jpayne@69: #define SQLITE_FCNTL_CKPT_START 39 jpayne@69: #define SQLITE_FCNTL_EXTERNAL_READER 40 jpayne@69: #define SQLITE_FCNTL_CKSM_FILE 41 jpayne@69: #define SQLITE_FCNTL_RESET_CACHE 42 jpayne@69: jpayne@69: /* deprecated names */ jpayne@69: #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE jpayne@69: #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE jpayne@69: #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Mutex Handle jpayne@69: ** jpayne@69: ** The mutex module within SQLite defines [sqlite3_mutex] to be an jpayne@69: ** abstract type for a mutex object. The SQLite core never looks jpayne@69: ** at the internal representation of an [sqlite3_mutex]. It only jpayne@69: ** deals with pointers to the [sqlite3_mutex] object. jpayne@69: ** jpayne@69: ** Mutexes are created using [sqlite3_mutex_alloc()]. jpayne@69: */ jpayne@69: typedef struct sqlite3_mutex sqlite3_mutex; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Loadable Extension Thunk jpayne@69: ** jpayne@69: ** A pointer to the opaque sqlite3_api_routines structure is passed as jpayne@69: ** the third parameter to entry points of [loadable extensions]. This jpayne@69: ** structure must be typedefed in order to work around compiler warnings jpayne@69: ** on some platforms. jpayne@69: */ jpayne@69: typedef struct sqlite3_api_routines sqlite3_api_routines; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: File Name jpayne@69: ** jpayne@69: ** Type [sqlite3_filename] is used by SQLite to pass filenames to the jpayne@69: ** xOpen method of a [VFS]. It may be cast to (const char*) and treated jpayne@69: ** as a normal, nul-terminated, UTF-8 buffer containing the filename, but jpayne@69: ** may also be passed to special APIs such as: jpayne@69: ** jpayne@69: ** jpayne@69: */ jpayne@69: typedef const char *sqlite3_filename; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: OS Interface Object jpayne@69: ** jpayne@69: ** An instance of the sqlite3_vfs object defines the interface between jpayne@69: ** the SQLite core and the underlying operating system. The "vfs" jpayne@69: ** in the name of the object stands for "virtual file system". See jpayne@69: ** the [VFS | VFS documentation] for further information. jpayne@69: ** jpayne@69: ** The VFS interface is sometimes extended by adding new methods onto jpayne@69: ** the end. Each time such an extension occurs, the iVersion field jpayne@69: ** is incremented. The iVersion value started out as 1 in jpayne@69: ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 jpayne@69: ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased jpayne@69: ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields jpayne@69: ** may be appended to the sqlite3_vfs object and the iVersion value jpayne@69: ** may increase again in future versions of SQLite. jpayne@69: ** Note that due to an oversight, the structure jpayne@69: ** of the sqlite3_vfs object changed in the transition from jpayne@69: ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] jpayne@69: ** and yet the iVersion field was not increased. jpayne@69: ** jpayne@69: ** The szOsFile field is the size of the subclassed [sqlite3_file] jpayne@69: ** structure used by this VFS. mxPathname is the maximum length of jpayne@69: ** a pathname in this VFS. jpayne@69: ** jpayne@69: ** Registered sqlite3_vfs objects are kept on a linked list formed by jpayne@69: ** the pNext pointer. The [sqlite3_vfs_register()] jpayne@69: ** and [sqlite3_vfs_unregister()] interfaces manage this list jpayne@69: ** in a thread-safe way. The [sqlite3_vfs_find()] interface jpayne@69: ** searches the list. Neither the application code nor the VFS jpayne@69: ** implementation should use the pNext pointer. jpayne@69: ** jpayne@69: ** The pNext field is the only field in the sqlite3_vfs jpayne@69: ** structure that SQLite will ever modify. SQLite will only access jpayne@69: ** or modify this field while holding a particular static mutex. jpayne@69: ** The application should never modify anything within the sqlite3_vfs jpayne@69: ** object once the object has been registered. jpayne@69: ** jpayne@69: ** The zName field holds the name of the VFS module. The name must jpayne@69: ** be unique across all VFS modules. jpayne@69: ** jpayne@69: ** [[sqlite3_vfs.xOpen]] jpayne@69: ** ^SQLite guarantees that the zFilename parameter to xOpen jpayne@69: ** is either a NULL pointer or string obtained jpayne@69: ** from xFullPathname() with an optional suffix added. jpayne@69: ** ^If a suffix is added to the zFilename parameter, it will jpayne@69: ** consist of a single "-" character followed by no more than jpayne@69: ** 11 alphanumeric and/or "-" characters. jpayne@69: ** ^SQLite further guarantees that jpayne@69: ** the string will be valid and unchanged until xClose() is jpayne@69: ** called. Because of the previous sentence, jpayne@69: ** the [sqlite3_file] can safely store a pointer to the jpayne@69: ** filename if it needs to remember the filename for some reason. jpayne@69: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen jpayne@69: ** must invent its own temporary name for the file. ^Whenever the jpayne@69: ** xFilename parameter is NULL it will also be the case that the jpayne@69: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. jpayne@69: ** jpayne@69: ** The flags argument to xOpen() includes all bits set in jpayne@69: ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] jpayne@69: ** or [sqlite3_open16()] is used, then flags includes at least jpayne@69: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. jpayne@69: ** If xOpen() opens a file read-only then it sets *pOutFlags to jpayne@69: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. jpayne@69: ** jpayne@69: ** ^(SQLite will also add one of the following flags to the xOpen() jpayne@69: ** call, depending on the object being opened: jpayne@69: ** jpayne@69: ** )^ jpayne@69: ** jpayne@69: ** The file I/O implementation can use the object type flags to jpayne@69: ** change the way it deals with files. For example, an application jpayne@69: ** that does not care about crash recovery or rollback might make jpayne@69: ** the open of a journal file a no-op. Writes to this journal would jpayne@69: ** also be no-ops, and any attempt to read the journal would return jpayne@69: ** SQLITE_IOERR. Or the implementation might recognize that a database jpayne@69: ** file will be doing page-aligned sector reads and writes in a random jpayne@69: ** order and set up its I/O subsystem accordingly. jpayne@69: ** jpayne@69: ** SQLite might also add one of the following flags to the xOpen method: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be jpayne@69: ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] jpayne@69: ** will be set for TEMP databases and their journals, transient jpayne@69: ** databases, and subjournals. jpayne@69: ** jpayne@69: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction jpayne@69: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly jpayne@69: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() jpayne@69: ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the jpayne@69: ** SQLITE_OPEN_CREATE, is used to indicate that file should always jpayne@69: ** be created, and that it is an error if it already exists. jpayne@69: ** It is not used to indicate the file should be opened jpayne@69: ** for exclusive access. jpayne@69: ** jpayne@69: ** ^At least szOsFile bytes of memory are allocated by SQLite jpayne@69: ** to hold the [sqlite3_file] structure passed as the third jpayne@69: ** argument to xOpen. The xOpen method does not have to jpayne@69: ** allocate the structure; it should just fill it in. Note that jpayne@69: ** the xOpen method must set the sqlite3_file.pMethods to either jpayne@69: ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do jpayne@69: ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods jpayne@69: ** element will be valid after xOpen returns regardless of the success jpayne@69: ** or failure of the xOpen call. jpayne@69: ** jpayne@69: ** [[sqlite3_vfs.xAccess]] jpayne@69: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] jpayne@69: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to jpayne@69: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] jpayne@69: ** to test whether a file is at least readable. The SQLITE_ACCESS_READ jpayne@69: ** flag is never actually used and is not implemented in the built-in jpayne@69: ** VFSes of SQLite. The file is named by the second argument and can be a jpayne@69: ** directory. The xAccess method returns [SQLITE_OK] on success or some jpayne@69: ** non-zero error code if there is an I/O error or if the name of jpayne@69: ** the file given in the second argument is illegal. If SQLITE_OK jpayne@69: ** is returned, then non-zero or zero is written into *pResOut to indicate jpayne@69: ** whether or not the file is accessible. jpayne@69: ** jpayne@69: ** ^SQLite will always allocate at least mxPathname+1 bytes for the jpayne@69: ** output buffer xFullPathname. The exact size of the output buffer jpayne@69: ** is also passed as a parameter to both methods. If the output buffer jpayne@69: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is jpayne@69: ** handled as a fatal error by SQLite, vfs implementations should endeavor jpayne@69: ** to prevent this by setting mxPathname to a sufficiently large value. jpayne@69: ** jpayne@69: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() jpayne@69: ** interfaces are not strictly a part of the filesystem, but they are jpayne@69: ** included in the VFS structure for completeness. jpayne@69: ** The xRandomness() function attempts to return nBytes bytes jpayne@69: ** of good-quality randomness into zOut. The return value is jpayne@69: ** the actual number of bytes of randomness obtained. jpayne@69: ** The xSleep() method causes the calling thread to sleep for at jpayne@69: ** least the number of microseconds given. ^The xCurrentTime() jpayne@69: ** method returns a Julian Day Number for the current date and time as jpayne@69: ** a floating point value. jpayne@69: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian jpayne@69: ** Day Number multiplied by 86400000 (the number of milliseconds in jpayne@69: ** a 24-hour day). jpayne@69: ** ^SQLite will use the xCurrentTimeInt64() method to get the current jpayne@69: ** date and time if that method is available (if iVersion is 2 or jpayne@69: ** greater and the function pointer is not NULL) and will fall back jpayne@69: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. jpayne@69: ** jpayne@69: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces jpayne@69: ** are not used by the SQLite core. These optional interfaces are provided jpayne@69: ** by some VFSes to facilitate testing of the VFS code. By overriding jpayne@69: ** system calls with functions under its control, a test program can jpayne@69: ** simulate faults and error conditions that would otherwise be difficult jpayne@69: ** or impossible to induce. The set of system calls that can be overridden jpayne@69: ** varies from one VFS to another, and from one version of the same VFS to the jpayne@69: ** next. Applications that use these interfaces must be prepared for any jpayne@69: ** or all of these interfaces to be NULL or for their behavior to change jpayne@69: ** from one release to the next. Applications must not attempt to access jpayne@69: ** any of these methods if the iVersion of the VFS is less than 3. jpayne@69: */ jpayne@69: typedef struct sqlite3_vfs sqlite3_vfs; jpayne@69: typedef void (*sqlite3_syscall_ptr)(void); jpayne@69: struct sqlite3_vfs { jpayne@69: int iVersion; /* Structure version number (currently 3) */ jpayne@69: int szOsFile; /* Size of subclassed sqlite3_file */ jpayne@69: int mxPathname; /* Maximum file pathname length */ jpayne@69: sqlite3_vfs *pNext; /* Next registered VFS */ jpayne@69: const char *zName; /* Name of this virtual file system */ jpayne@69: void *pAppData; /* Pointer to application-specific data */ jpayne@69: int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*, jpayne@69: int flags, int *pOutFlags); jpayne@69: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); jpayne@69: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); jpayne@69: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); jpayne@69: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); jpayne@69: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); jpayne@69: void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); jpayne@69: void (*xDlClose)(sqlite3_vfs*, void*); jpayne@69: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); jpayne@69: int (*xSleep)(sqlite3_vfs*, int microseconds); jpayne@69: int (*xCurrentTime)(sqlite3_vfs*, double*); jpayne@69: int (*xGetLastError)(sqlite3_vfs*, int, char *); jpayne@69: /* jpayne@69: ** The methods above are in version 1 of the sqlite_vfs object jpayne@69: ** definition. Those that follow are added in version 2 or later jpayne@69: */ jpayne@69: int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); jpayne@69: /* jpayne@69: ** The methods above are in versions 1 and 2 of the sqlite_vfs object. jpayne@69: ** Those below are for version 3 and greater. jpayne@69: */ jpayne@69: int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); jpayne@69: sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); jpayne@69: const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); jpayne@69: /* jpayne@69: ** The methods above are in versions 1 through 3 of the sqlite_vfs object. jpayne@69: ** New fields may be appended in future versions. The iVersion jpayne@69: ** value will increment whenever this happens. jpayne@69: */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for the xAccess VFS method jpayne@69: ** jpayne@69: ** These integer constants can be used as the third parameter to jpayne@69: ** the xAccess method of an [sqlite3_vfs] object. They determine jpayne@69: ** what kind of permissions the xAccess method is looking for. jpayne@69: ** With SQLITE_ACCESS_EXISTS, the xAccess method jpayne@69: ** simply checks whether the file exists. jpayne@69: ** With SQLITE_ACCESS_READWRITE, the xAccess method jpayne@69: ** checks whether the named directory is both readable and writable jpayne@69: ** (in other words, if files can be added, removed, and renamed within jpayne@69: ** the directory). jpayne@69: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the jpayne@69: ** [temp_store_directory pragma], though this could change in a future jpayne@69: ** release of SQLite. jpayne@69: ** With SQLITE_ACCESS_READ, the xAccess method jpayne@69: ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is jpayne@69: ** currently unused, though it might be used in a future release of jpayne@69: ** SQLite. jpayne@69: */ jpayne@69: #define SQLITE_ACCESS_EXISTS 0 jpayne@69: #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ jpayne@69: #define SQLITE_ACCESS_READ 2 /* Unused */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for the xShmLock VFS method jpayne@69: ** jpayne@69: ** These integer constants define the various locking operations jpayne@69: ** allowed by the xShmLock method of [sqlite3_io_methods]. The jpayne@69: ** following are the only legal combinations of flags to the jpayne@69: ** xShmLock method: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as jpayne@69: ** was given on the corresponding lock. jpayne@69: ** jpayne@69: ** The xShmLock method can transition between unlocked and SHARED or jpayne@69: ** between unlocked and EXCLUSIVE. It cannot transition between SHARED jpayne@69: ** and EXCLUSIVE. jpayne@69: */ jpayne@69: #define SQLITE_SHM_UNLOCK 1 jpayne@69: #define SQLITE_SHM_LOCK 2 jpayne@69: #define SQLITE_SHM_SHARED 4 jpayne@69: #define SQLITE_SHM_EXCLUSIVE 8 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Maximum xShmLock index jpayne@69: ** jpayne@69: ** The xShmLock method on [sqlite3_io_methods] may use values jpayne@69: ** between 0 and this upper bound as its "offset" argument. jpayne@69: ** The SQLite core will never attempt to acquire or release a jpayne@69: ** lock outside of this range jpayne@69: */ jpayne@69: #define SQLITE_SHM_NLOCK 8 jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Initialize The SQLite Library jpayne@69: ** jpayne@69: ** ^The sqlite3_initialize() routine initializes the jpayne@69: ** SQLite library. ^The sqlite3_shutdown() routine jpayne@69: ** deallocates any resources that were allocated by sqlite3_initialize(). jpayne@69: ** These routines are designed to aid in process initialization and jpayne@69: ** shutdown on embedded systems. Workstation applications using jpayne@69: ** SQLite normally do not need to invoke either of these routines. jpayne@69: ** jpayne@69: ** A call to sqlite3_initialize() is an "effective" call if it is jpayne@69: ** the first time sqlite3_initialize() is invoked during the lifetime of jpayne@69: ** the process, or if it is the first time sqlite3_initialize() is invoked jpayne@69: ** following a call to sqlite3_shutdown(). ^(Only an effective call jpayne@69: ** of sqlite3_initialize() does any initialization. All other calls jpayne@69: ** are harmless no-ops.)^ jpayne@69: ** jpayne@69: ** A call to sqlite3_shutdown() is an "effective" call if it is the first jpayne@69: ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only jpayne@69: ** an effective call to sqlite3_shutdown() does any deinitialization. jpayne@69: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ jpayne@69: ** jpayne@69: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() jpayne@69: ** is not. The sqlite3_shutdown() interface must only be called from a jpayne@69: ** single thread. All open [database connections] must be closed and all jpayne@69: ** other SQLite resources must be deallocated prior to invoking jpayne@69: ** sqlite3_shutdown(). jpayne@69: ** jpayne@69: ** Among other things, ^sqlite3_initialize() will invoke jpayne@69: ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() jpayne@69: ** will invoke sqlite3_os_end(). jpayne@69: ** jpayne@69: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. jpayne@69: ** ^If for some reason, sqlite3_initialize() is unable to initialize jpayne@69: ** the library (perhaps it is unable to allocate a needed resource such jpayne@69: ** as a mutex) it returns an [error code] other than [SQLITE_OK]. jpayne@69: ** jpayne@69: ** ^The sqlite3_initialize() routine is called internally by many other jpayne@69: ** SQLite interfaces so that an application usually does not need to jpayne@69: ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] jpayne@69: ** calls sqlite3_initialize() so the SQLite library will be automatically jpayne@69: ** initialized when [sqlite3_open()] is called if it has not be initialized jpayne@69: ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] jpayne@69: ** compile-time option, then the automatic calls to sqlite3_initialize() jpayne@69: ** are omitted and the application must call sqlite3_initialize() directly jpayne@69: ** prior to using any other SQLite interface. For maximum portability, jpayne@69: ** it is recommended that applications always invoke sqlite3_initialize() jpayne@69: ** directly prior to using any other SQLite interface. Future releases jpayne@69: ** of SQLite may require this. In other words, the behavior exhibited jpayne@69: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the jpayne@69: ** default behavior in some future release of SQLite. jpayne@69: ** jpayne@69: ** The sqlite3_os_init() routine does operating-system specific jpayne@69: ** initialization of the SQLite library. The sqlite3_os_end() jpayne@69: ** routine undoes the effect of sqlite3_os_init(). Typical tasks jpayne@69: ** performed by these routines include allocation or deallocation jpayne@69: ** of static resources, initialization of global variables, jpayne@69: ** setting up a default [sqlite3_vfs] module, or setting up jpayne@69: ** a default configuration using [sqlite3_config()]. jpayne@69: ** jpayne@69: ** The application should never invoke either sqlite3_os_init() jpayne@69: ** or sqlite3_os_end() directly. The application should only invoke jpayne@69: ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() jpayne@69: ** interface is called automatically by sqlite3_initialize() and jpayne@69: ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate jpayne@69: ** implementations for sqlite3_os_init() and sqlite3_os_end() jpayne@69: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. jpayne@69: ** When [custom builds | built for other platforms] jpayne@69: ** (using the [SQLITE_OS_OTHER=1] compile-time jpayne@69: ** option) the application must supply a suitable implementation for jpayne@69: ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied jpayne@69: ** implementation of sqlite3_os_init() or sqlite3_os_end() jpayne@69: ** must return [SQLITE_OK] on success and some other [error code] upon jpayne@69: ** failure. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_initialize(void); jpayne@69: SQLITE_API int sqlite3_shutdown(void); jpayne@69: SQLITE_API int sqlite3_os_init(void); jpayne@69: SQLITE_API int sqlite3_os_end(void); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configuring The SQLite Library jpayne@69: ** jpayne@69: ** The sqlite3_config() interface is used to make global configuration jpayne@69: ** changes to SQLite in order to tune SQLite to the specific needs of jpayne@69: ** the application. The default configuration is recommended for most jpayne@69: ** applications and so this routine is usually not necessary. It is jpayne@69: ** provided to support rare applications with unusual needs. jpayne@69: ** jpayne@69: ** The sqlite3_config() interface is not threadsafe. The application jpayne@69: ** must ensure that no other SQLite interfaces are invoked by other jpayne@69: ** threads while sqlite3_config() is running. jpayne@69: ** jpayne@69: ** The first argument to sqlite3_config() is an integer jpayne@69: ** [configuration option] that determines jpayne@69: ** what property of SQLite is to be configured. Subsequent arguments jpayne@69: ** vary depending on the [configuration option] jpayne@69: ** in the first argument. jpayne@69: ** jpayne@69: ** For most configuration options, the sqlite3_config() interface jpayne@69: ** may only be invoked prior to library initialization using jpayne@69: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. jpayne@69: ** The exceptional configuration options that may be invoked at any time jpayne@69: ** are called "anytime configuration options". jpayne@69: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before jpayne@69: ** [sqlite3_shutdown()] with a first argument that is not an anytime jpayne@69: ** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE. jpayne@69: ** Note, however, that ^sqlite3_config() can be called as part of the jpayne@69: ** implementation of an application-defined [sqlite3_os_init()]. jpayne@69: ** jpayne@69: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. jpayne@69: ** ^If the option is unknown or SQLite is unable to set the option jpayne@69: ** then this routine returns a non-zero [error code]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_config(int, ...); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configure database connections jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** The sqlite3_db_config() interface is used to make configuration jpayne@69: ** changes to a [database connection]. The interface is similar to jpayne@69: ** [sqlite3_config()] except that the changes apply to a single jpayne@69: ** [database connection] (specified in the first argument). jpayne@69: ** jpayne@69: ** The second argument to sqlite3_db_config(D,V,...) is the jpayne@69: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code jpayne@69: ** that indicates what aspect of the [database connection] is being configured. jpayne@69: ** Subsequent arguments vary depending on the configuration verb. jpayne@69: ** jpayne@69: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if jpayne@69: ** the call is considered successful. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Memory Allocation Routines jpayne@69: ** jpayne@69: ** An instance of this object defines the interface between SQLite jpayne@69: ** and low-level memory allocation routines. jpayne@69: ** jpayne@69: ** This object is used in only one place in the SQLite interface. jpayne@69: ** A pointer to an instance of this object is the argument to jpayne@69: ** [sqlite3_config()] when the configuration option is jpayne@69: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. jpayne@69: ** By creating an instance of this object jpayne@69: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) jpayne@69: ** during configuration, an application can specify an alternative jpayne@69: ** memory allocation subsystem for SQLite to use for all of its jpayne@69: ** dynamic memory needs. jpayne@69: ** jpayne@69: ** Note that SQLite comes with several [built-in memory allocators] jpayne@69: ** that are perfectly adequate for the overwhelming majority of applications jpayne@69: ** and that this object is only useful to a tiny minority of applications jpayne@69: ** with specialized memory allocation requirements. This object is jpayne@69: ** also used during testing of SQLite in order to specify an alternative jpayne@69: ** memory allocator that simulates memory out-of-memory conditions in jpayne@69: ** order to verify that SQLite recovers gracefully from such jpayne@69: ** conditions. jpayne@69: ** jpayne@69: ** The xMalloc, xRealloc, and xFree methods must work like the jpayne@69: ** malloc(), realloc() and free() functions from the standard C library. jpayne@69: ** ^SQLite guarantees that the second argument to jpayne@69: ** xRealloc is always a value returned by a prior call to xRoundup. jpayne@69: ** jpayne@69: ** xSize should return the allocated size of a memory allocation jpayne@69: ** previously obtained from xMalloc or xRealloc. The allocated size jpayne@69: ** is always at least as big as the requested size but may be larger. jpayne@69: ** jpayne@69: ** The xRoundup method returns what would be the allocated size of jpayne@69: ** a memory allocation given a particular requested size. Most memory jpayne@69: ** allocators round up memory allocations at least to the next multiple jpayne@69: ** of 8. Some allocators round up to a larger multiple or to a power of 2. jpayne@69: ** Every memory allocation request coming in through [sqlite3_malloc()] jpayne@69: ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, jpayne@69: ** that causes the corresponding memory allocation to fail. jpayne@69: ** jpayne@69: ** The xInit method initializes the memory allocator. For example, jpayne@69: ** it might allocate any required mutexes or initialize internal data jpayne@69: ** structures. The xShutdown method is invoked (indirectly) by jpayne@69: ** [sqlite3_shutdown()] and should deallocate any resources acquired jpayne@69: ** by xInit. The pAppData pointer is used as the only parameter to jpayne@69: ** xInit and xShutdown. jpayne@69: ** jpayne@69: ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes jpayne@69: ** the xInit method, so the xInit method need not be threadsafe. The jpayne@69: ** xShutdown method is only called from [sqlite3_shutdown()] so it does jpayne@69: ** not need to be threadsafe either. For all other methods, SQLite jpayne@69: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the jpayne@69: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which jpayne@69: ** it is by default) and so the methods are automatically serialized. jpayne@69: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other jpayne@69: ** methods must be threadsafe or else make their own arrangements for jpayne@69: ** serialization. jpayne@69: ** jpayne@69: ** SQLite will never invoke xInit() more than once without an intervening jpayne@69: ** call to xShutdown(). jpayne@69: */ jpayne@69: typedef struct sqlite3_mem_methods sqlite3_mem_methods; jpayne@69: struct sqlite3_mem_methods { jpayne@69: void *(*xMalloc)(int); /* Memory allocation function */ jpayne@69: void (*xFree)(void*); /* Free a prior allocation */ jpayne@69: void *(*xRealloc)(void*,int); /* Resize an allocation */ jpayne@69: int (*xSize)(void*); /* Return the size of an allocation */ jpayne@69: int (*xRoundup)(int); /* Round up request size to allocation size */ jpayne@69: int (*xInit)(void*); /* Initialize the memory allocator */ jpayne@69: void (*xShutdown)(void*); /* Deinitialize the memory allocator */ jpayne@69: void *pAppData; /* Argument to xInit() and xShutdown() */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configuration Options jpayne@69: ** KEYWORDS: {configuration option} jpayne@69: ** jpayne@69: ** These constants are the available integer configuration options that jpayne@69: ** can be passed as the first argument to the [sqlite3_config()] interface. jpayne@69: ** jpayne@69: ** Most of the configuration options for sqlite3_config() jpayne@69: ** will only work if invoked prior to [sqlite3_initialize()] or after jpayne@69: ** [sqlite3_shutdown()]. The few exceptions to this rule are called jpayne@69: ** "anytime configuration options". jpayne@69: ** ^Calling [sqlite3_config()] with a first argument that is not an jpayne@69: ** anytime configuration option in between calls to [sqlite3_initialize()] and jpayne@69: ** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE. jpayne@69: ** jpayne@69: ** The set of anytime configuration options can change (by insertions jpayne@69: ** and/or deletions) from one release of SQLite to the next. jpayne@69: ** As of SQLite version 3.42.0, the complete set of anytime configuration jpayne@69: ** options is: jpayne@69: ** jpayne@69: ** jpayne@69: ** New configuration options may be added in future releases of SQLite. jpayne@69: ** Existing configuration options might be discontinued. Applications jpayne@69: ** should check the return code from [sqlite3_config()] to make sure that jpayne@69: ** the call worked. The [sqlite3_config()] interface will return a jpayne@69: ** non-zero [error code] if a discontinued or unsupported configuration option jpayne@69: ** is invoked. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_CONFIG_SINGLETHREAD]]
SQLITE_CONFIG_SINGLETHREAD
jpayne@69: **
There are no arguments to this option. ^This option sets the jpayne@69: ** [threading mode] to Single-thread. In other words, it disables jpayne@69: ** all mutexing and puts SQLite into a mode where it can only be used jpayne@69: ** by a single thread. ^If SQLite is compiled with jpayne@69: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then jpayne@69: ** it is not possible to change the [threading mode] from its default jpayne@69: ** value of Single-thread and so [sqlite3_config()] will return jpayne@69: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD jpayne@69: ** configuration option.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MULTITHREAD]]
SQLITE_CONFIG_MULTITHREAD
jpayne@69: **
There are no arguments to this option. ^This option sets the jpayne@69: ** [threading mode] to Multi-thread. In other words, it disables jpayne@69: ** mutexing on [database connection] and [prepared statement] objects. jpayne@69: ** The application is responsible for serializing access to jpayne@69: ** [database connections] and [prepared statements]. But other mutexes jpayne@69: ** are enabled so that SQLite will be safe to use in a multi-threaded jpayne@69: ** environment as long as no two threads attempt to use the same jpayne@69: ** [database connection] at the same time. ^If SQLite is compiled with jpayne@69: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then jpayne@69: ** it is not possible to set the Multi-thread [threading mode] and jpayne@69: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the jpayne@69: ** SQLITE_CONFIG_MULTITHREAD configuration option.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_SERIALIZED]]
SQLITE_CONFIG_SERIALIZED
jpayne@69: **
There are no arguments to this option. ^This option sets the jpayne@69: ** [threading mode] to Serialized. In other words, this option enables jpayne@69: ** all mutexes including the recursive jpayne@69: ** mutexes on [database connection] and [prepared statement] objects. jpayne@69: ** In this mode (which is the default when SQLite is compiled with jpayne@69: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access jpayne@69: ** to [database connections] and [prepared statements] so that the jpayne@69: ** application is free to use the same [database connection] or the jpayne@69: ** same [prepared statement] in different threads at the same time. jpayne@69: ** ^If SQLite is compiled with jpayne@69: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then jpayne@69: ** it is not possible to set the Serialized [threading mode] and jpayne@69: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the jpayne@69: ** SQLITE_CONFIG_SERIALIZED configuration option.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MALLOC]]
SQLITE_CONFIG_MALLOC
jpayne@69: **
^(The SQLITE_CONFIG_MALLOC option takes a single argument which is jpayne@69: ** a pointer to an instance of the [sqlite3_mem_methods] structure. jpayne@69: ** The argument specifies jpayne@69: ** alternative low-level memory allocation routines to be used in place of jpayne@69: ** the memory allocation routines built into SQLite.)^ ^SQLite makes jpayne@69: ** its own private copy of the content of the [sqlite3_mem_methods] structure jpayne@69: ** before the [sqlite3_config()] call returns.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_GETMALLOC]]
SQLITE_CONFIG_GETMALLOC
jpayne@69: **
^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which jpayne@69: ** is a pointer to an instance of the [sqlite3_mem_methods] structure. jpayne@69: ** The [sqlite3_mem_methods] jpayne@69: ** structure is filled with the currently defined memory allocation routines.)^ jpayne@69: ** This option can be used to overload the default memory allocation jpayne@69: ** routines with a wrapper that simulations memory allocation failure or jpayne@69: ** tracks memory usage, for example.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_SMALL_MALLOC]]
SQLITE_CONFIG_SMALL_MALLOC
jpayne@69: **
^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of jpayne@69: ** type int, interpreted as a boolean, which if true provides a hint to jpayne@69: ** SQLite that it should avoid large memory allocations if possible. jpayne@69: ** SQLite will run faster if it is free to make large memory allocations, jpayne@69: ** but some application might prefer to run slower in exchange for jpayne@69: ** guarantees about memory fragmentation that are possible if large jpayne@69: ** allocations are avoided. This hint is normally off. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MEMSTATUS]]
SQLITE_CONFIG_MEMSTATUS
jpayne@69: **
^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, jpayne@69: ** interpreted as a boolean, which enables or disables the collection of jpayne@69: ** memory allocation statistics. ^(When memory allocation statistics are jpayne@69: ** disabled, the following SQLite interfaces become non-operational: jpayne@69: **
    jpayne@69: **
  • [sqlite3_hard_heap_limit64()] jpayne@69: **
  • [sqlite3_memory_used()] jpayne@69: **
  • [sqlite3_memory_highwater()] jpayne@69: **
  • [sqlite3_soft_heap_limit64()] jpayne@69: **
  • [sqlite3_status64()] jpayne@69: **
)^ jpayne@69: ** ^Memory allocation statistics are enabled by default unless SQLite is jpayne@69: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory jpayne@69: ** allocation statistics are disabled by default. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_SCRATCH]]
SQLITE_CONFIG_SCRATCH
jpayne@69: **
The SQLITE_CONFIG_SCRATCH option is no longer used. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_PAGECACHE]]
SQLITE_CONFIG_PAGECACHE
jpayne@69: **
^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool jpayne@69: ** that SQLite can use for the database page cache with the default page jpayne@69: ** cache implementation. jpayne@69: ** This configuration option is a no-op if an application-defined page jpayne@69: ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. jpayne@69: ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to jpayne@69: ** 8-byte aligned memory (pMem), the size of each page cache line (sz), jpayne@69: ** and the number of cache lines (N). jpayne@69: ** The sz argument should be the size of the largest database page jpayne@69: ** (a power of two between 512 and 65536) plus some extra bytes for each jpayne@69: ** page header. ^The number of extra bytes needed by the page header jpayne@69: ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. jpayne@69: ** ^It is harmless, apart from the wasted memory, jpayne@69: ** for the sz parameter to be larger than necessary. The pMem jpayne@69: ** argument must be either a NULL pointer or a pointer to an 8-byte jpayne@69: ** aligned block of memory of at least sz*N bytes, otherwise jpayne@69: ** subsequent behavior is undefined. jpayne@69: ** ^When pMem is not NULL, SQLite will strive to use the memory provided jpayne@69: ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if jpayne@69: ** a page cache line is larger than sz bytes or if all of the pMem buffer jpayne@69: ** is exhausted. jpayne@69: ** ^If pMem is NULL and N is non-zero, then each database connection jpayne@69: ** does an initial bulk allocation for page cache memory jpayne@69: ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or jpayne@69: ** of -1024*N bytes if N is negative, . ^If additional jpayne@69: ** page cache memory is needed beyond what is provided by the initial jpayne@69: ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each jpayne@69: ** additional cache line.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_HEAP]]
SQLITE_CONFIG_HEAP
jpayne@69: **
^The SQLITE_CONFIG_HEAP option specifies a static memory buffer jpayne@69: ** that SQLite will use for all of its dynamic memory allocation needs jpayne@69: ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. jpayne@69: ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled jpayne@69: ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns jpayne@69: ** [SQLITE_ERROR] if invoked otherwise. jpayne@69: ** ^There are three arguments to SQLITE_CONFIG_HEAP: jpayne@69: ** An 8-byte aligned pointer to the memory, jpayne@69: ** the number of bytes in the memory buffer, and the minimum allocation size. jpayne@69: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts jpayne@69: ** to using its default memory allocator (the system malloc() implementation), jpayne@69: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the jpayne@69: ** memory pointer is not NULL then the alternative memory jpayne@69: ** allocator is engaged to handle all of SQLites memory allocation needs. jpayne@69: ** The first pointer (the memory pointer) must be aligned to an 8-byte jpayne@69: ** boundary or subsequent behavior of SQLite will be undefined. jpayne@69: ** The minimum allocation size is capped at 2**12. Reasonable values jpayne@69: ** for the minimum allocation size are 2**5 through 2**8.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MUTEX]]
SQLITE_CONFIG_MUTEX
jpayne@69: **
^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a jpayne@69: ** pointer to an instance of the [sqlite3_mutex_methods] structure. jpayne@69: ** The argument specifies alternative low-level mutex routines to be used jpayne@69: ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of jpayne@69: ** the content of the [sqlite3_mutex_methods] structure before the call to jpayne@69: ** [sqlite3_config()] returns. ^If SQLite is compiled with jpayne@69: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then jpayne@69: ** the entire mutexing subsystem is omitted from the build and hence calls to jpayne@69: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will jpayne@69: ** return [SQLITE_ERROR].
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_GETMUTEX]]
SQLITE_CONFIG_GETMUTEX
jpayne@69: **
^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which jpayne@69: ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The jpayne@69: ** [sqlite3_mutex_methods] jpayne@69: ** structure is filled with the currently defined mutex routines.)^ jpayne@69: ** This option can be used to overload the default mutex allocation jpayne@69: ** routines with a wrapper used to track mutex usage for performance jpayne@69: ** profiling or testing, for example. ^If SQLite is compiled with jpayne@69: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then jpayne@69: ** the entire mutexing subsystem is omitted from the build and hence calls to jpayne@69: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will jpayne@69: ** return [SQLITE_ERROR].
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_LOOKASIDE]]
SQLITE_CONFIG_LOOKASIDE
jpayne@69: **
^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine jpayne@69: ** the default size of lookaside memory on each [database connection]. jpayne@69: ** The first argument is the jpayne@69: ** size of each lookaside buffer slot and the second is the number of jpayne@69: ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE jpayne@69: ** sets the default lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] jpayne@69: ** option to [sqlite3_db_config()] can be used to change the lookaside jpayne@69: ** configuration on individual connections.)^
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_PCACHE2]]
SQLITE_CONFIG_PCACHE2
jpayne@69: **
^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is jpayne@69: ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies jpayne@69: ** the interface to a custom page cache implementation.)^ jpayne@69: ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_GETPCACHE2]]
SQLITE_CONFIG_GETPCACHE2
jpayne@69: **
^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which jpayne@69: ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of jpayne@69: ** the current page cache implementation into that object.)^
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_LOG]]
SQLITE_CONFIG_LOG
jpayne@69: **
The SQLITE_CONFIG_LOG option is used to configure the SQLite jpayne@69: ** global [error log]. jpayne@69: ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a jpayne@69: ** function with a call signature of void(*)(void*,int,const char*), jpayne@69: ** and a pointer to void. ^If the function pointer is not NULL, it is jpayne@69: ** invoked by [sqlite3_log()] to process each logging event. ^If the jpayne@69: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. jpayne@69: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is jpayne@69: ** passed through as the first parameter to the application-defined logger jpayne@69: ** function whenever that function is invoked. ^The second parameter to jpayne@69: ** the logger function is a copy of the first parameter to the corresponding jpayne@69: ** [sqlite3_log()] call and is intended to be a [result code] or an jpayne@69: ** [extended result code]. ^The third parameter passed to the logger is jpayne@69: ** log message after formatting via [sqlite3_snprintf()]. jpayne@69: ** The SQLite logging interface is not reentrant; the logger function jpayne@69: ** supplied by the application must not invoke any SQLite interface. jpayne@69: ** In a multi-threaded application, the application-defined logger jpayne@69: ** function must be threadsafe.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_URI]]
SQLITE_CONFIG_URI jpayne@69: **
^(The SQLITE_CONFIG_URI option takes a single argument of type int. jpayne@69: ** If non-zero, then URI handling is globally enabled. If the parameter is zero, jpayne@69: ** then URI handling is globally disabled.)^ ^If URI handling is globally jpayne@69: ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], jpayne@69: ** [sqlite3_open16()] or jpayne@69: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless jpayne@69: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database jpayne@69: ** connection is opened. ^If it is globally disabled, filenames are jpayne@69: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the jpayne@69: ** database connection is opened. ^(By default, URI handling is globally jpayne@69: ** disabled. The default value may be changed by compiling with the jpayne@69: ** [SQLITE_USE_URI] symbol defined.)^ jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]]
SQLITE_CONFIG_COVERING_INDEX_SCAN jpayne@69: **
^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer jpayne@69: ** argument which is interpreted as a boolean in order to enable or disable jpayne@69: ** the use of covering indices for full table scans in the query optimizer. jpayne@69: ** ^The default setting is determined jpayne@69: ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" jpayne@69: ** if that compile-time option is omitted. jpayne@69: ** The ability to disable the use of covering indices for full table scans jpayne@69: ** is because some incorrectly coded legacy applications might malfunction jpayne@69: ** when the optimization is enabled. Providing the ability to jpayne@69: ** disable the optimization allows the older, buggy application code to work jpayne@69: ** without change even with newer versions of SQLite. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] jpayne@69: **
SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE jpayne@69: **
These options are obsolete and should not be used by new code. jpayne@69: ** They are retained for backwards compatibility but are now no-ops. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_SQLLOG]] jpayne@69: **
SQLITE_CONFIG_SQLLOG jpayne@69: **
This option is only available if sqlite is compiled with the jpayne@69: ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should jpayne@69: ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). jpayne@69: ** The second should be of type (void*). The callback is invoked by the library jpayne@69: ** in three separate circumstances, identified by the value passed as the jpayne@69: ** fourth parameter. If the fourth parameter is 0, then the database connection jpayne@69: ** passed as the second argument has just been opened. The third argument jpayne@69: ** points to a buffer containing the name of the main database file. If the jpayne@69: ** fourth parameter is 1, then the SQL statement that the third parameter jpayne@69: ** points to has just been executed. Or, if the fourth parameter is 2, then jpayne@69: ** the connection being passed as the second parameter is being closed. The jpayne@69: ** third parameter is passed NULL In this case. An example of using this jpayne@69: ** configuration option can be seen in the "test_sqllog.c" source file in jpayne@69: ** the canonical SQLite source tree.
jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MMAP_SIZE]] jpayne@69: **
SQLITE_CONFIG_MMAP_SIZE jpayne@69: **
^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values jpayne@69: ** that are the default mmap size limit (the default setting for jpayne@69: ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. jpayne@69: ** ^The default setting can be overridden by each database connection using jpayne@69: ** either the [PRAGMA mmap_size] command, or by using the jpayne@69: ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size jpayne@69: ** will be silently truncated if necessary so that it does not exceed the jpayne@69: ** compile-time maximum mmap size set by the jpayne@69: ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ jpayne@69: ** ^If either argument to this option is negative, then that argument is jpayne@69: ** changed to its compile-time default. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] jpayne@69: **
SQLITE_CONFIG_WIN32_HEAPSIZE jpayne@69: **
^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is jpayne@69: ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro jpayne@69: ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value jpayne@69: ** that specifies the maximum size of the created heap. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] jpayne@69: **
SQLITE_CONFIG_PCACHE_HDRSZ jpayne@69: **
^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which jpayne@69: ** is a pointer to an integer and writes into that integer the number of extra jpayne@69: ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. jpayne@69: ** The amount of extra space required can change depending on the compiler, jpayne@69: ** target platform, and SQLite version. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_PMASZ]] jpayne@69: **
SQLITE_CONFIG_PMASZ jpayne@69: **
^The SQLITE_CONFIG_PMASZ option takes a single parameter which jpayne@69: ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded jpayne@69: ** sorter to that integer. The default minimum PMA Size is set by the jpayne@69: ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched jpayne@69: ** to help with sort operations when multithreaded sorting jpayne@69: ** is enabled (using the [PRAGMA threads] command) and the amount of content jpayne@69: ** to be sorted exceeds the page size times the minimum of the jpayne@69: ** [PRAGMA cache_size] setting and this value. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] jpayne@69: **
SQLITE_CONFIG_STMTJRNL_SPILL jpayne@69: **
^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which jpayne@69: ** becomes the [statement journal] spill-to-disk threshold. jpayne@69: ** [Statement journals] are held in memory until their size (in bytes) jpayne@69: ** exceeds this threshold, at which point they are written to disk. jpayne@69: ** Or if the threshold is -1, statement journals are always held jpayne@69: ** exclusively in memory. jpayne@69: ** Since many statement journals never become large, setting the spill jpayne@69: ** threshold to a value such as 64KiB can greatly reduce the amount of jpayne@69: ** I/O required to support statement rollback. jpayne@69: ** The default value for this setting is controlled by the jpayne@69: ** [SQLITE_STMTJRNL_SPILL] compile-time option. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_SORTERREF_SIZE]] jpayne@69: **
SQLITE_CONFIG_SORTERREF_SIZE jpayne@69: **
The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter jpayne@69: ** of type (int) - the new value of the sorter-reference size threshold. jpayne@69: ** Usually, when SQLite uses an external sort to order records according jpayne@69: ** to an ORDER BY clause, all fields required by the caller are present in the jpayne@69: ** sorted records. However, if SQLite determines based on the declared type jpayne@69: ** of a table column that its values are likely to be very large - larger jpayne@69: ** than the configured sorter-reference size threshold - then a reference jpayne@69: ** is stored in each sorted record and the required column values loaded jpayne@69: ** from the database as records are returned in sorted order. The default jpayne@69: ** value for this option is to never use this optimization. Specifying a jpayne@69: ** negative value for this option restores the default behavior. jpayne@69: ** This option is only available if SQLite is compiled with the jpayne@69: ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] jpayne@69: **
SQLITE_CONFIG_MEMDB_MAXSIZE jpayne@69: **
The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter jpayne@69: ** [sqlite3_int64] parameter which is the default maximum size for an in-memory jpayne@69: ** database created using [sqlite3_deserialize()]. This default maximum jpayne@69: ** size can be adjusted up or down for individual databases using the jpayne@69: ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this jpayne@69: ** configuration setting is never used, then the default maximum is determined jpayne@69: ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that jpayne@69: ** compile-time option is not set, then the default maximum is 1073741824. jpayne@69: ** jpayne@69: ** [[SQLITE_CONFIG_ROWID_IN_VIEW]] jpayne@69: **
SQLITE_CONFIG_ROWID_IN_VIEW jpayne@69: **
The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability jpayne@69: ** for VIEWs to have a ROWID. The capability can only be enabled if SQLite is jpayne@69: ** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability jpayne@69: ** defaults to on. This configuration option queries the current setting or jpayne@69: ** changes the setting to off or on. The argument is a pointer to an integer. jpayne@69: ** If that integer initially holds a value of 1, then the ability for VIEWs to jpayne@69: ** have ROWIDs is activated. If the integer initially holds zero, then the jpayne@69: ** ability is deactivated. Any other initial value for the integer leaves the jpayne@69: ** setting unchanged. After changes, if any, the integer is written with jpayne@69: ** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off. If SQLite jpayne@69: ** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and jpayne@69: ** recommended case) then the integer is always filled with zero, regardless jpayne@69: ** if its initial value. jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ jpayne@69: #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ jpayne@69: #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ jpayne@69: #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ jpayne@69: #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ jpayne@69: #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ jpayne@69: #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ jpayne@69: #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ jpayne@69: #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ jpayne@69: #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ jpayne@69: #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ jpayne@69: /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ jpayne@69: #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ jpayne@69: #define SQLITE_CONFIG_PCACHE 14 /* no-op */ jpayne@69: #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ jpayne@69: #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ jpayne@69: #define SQLITE_CONFIG_URI 17 /* int */ jpayne@69: #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ jpayne@69: #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ jpayne@69: #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ jpayne@69: #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ jpayne@69: #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ jpayne@69: #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ jpayne@69: #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ jpayne@69: #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ jpayne@69: #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ jpayne@69: #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ jpayne@69: #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ jpayne@69: #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ jpayne@69: #define SQLITE_CONFIG_ROWID_IN_VIEW 30 /* int* */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Connection Configuration Options jpayne@69: ** jpayne@69: ** These constants are the available integer configuration options that jpayne@69: ** can be passed as the second argument to the [sqlite3_db_config()] interface. jpayne@69: ** jpayne@69: ** New configuration options may be added in future releases of SQLite. jpayne@69: ** Existing configuration options might be discontinued. Applications jpayne@69: ** should check the return code from [sqlite3_db_config()] to make sure that jpayne@69: ** the call worked. ^The [sqlite3_db_config()] interface will return a jpayne@69: ** non-zero [error code] if a discontinued or unsupported configuration option jpayne@69: ** is invoked. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_DBCONFIG_LOOKASIDE]] jpayne@69: **
SQLITE_DBCONFIG_LOOKASIDE
jpayne@69: **
^This option takes three additional arguments that determine the jpayne@69: ** [lookaside memory allocator] configuration for the [database connection]. jpayne@69: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a jpayne@69: ** pointer to a memory buffer to use for lookaside memory. jpayne@69: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb jpayne@69: ** may be NULL in which case SQLite will allocate the jpayne@69: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the jpayne@69: ** size of each lookaside buffer slot. ^The third argument is the number of jpayne@69: ** slots. The size of the buffer in the first argument must be greater than jpayne@69: ** or equal to the product of the second and third arguments. The buffer jpayne@69: ** must be aligned to an 8-byte boundary. ^If the second argument to jpayne@69: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally jpayne@69: ** rounded down to the next smaller multiple of 8. ^(The lookaside memory jpayne@69: ** configuration for a database connection can only be changed when that jpayne@69: ** connection is not currently using lookaside memory, or in other words jpayne@69: ** when the "current value" returned by jpayne@69: ** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero. jpayne@69: ** Any attempt to change the lookaside memory configuration when lookaside jpayne@69: ** memory is in use leaves the configuration unchanged and returns jpayne@69: ** [SQLITE_BUSY].)^
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] jpayne@69: **
SQLITE_DBCONFIG_ENABLE_FKEY
jpayne@69: **
^This option is used to enable or disable the enforcement of jpayne@69: ** [foreign key constraints]. There should be two additional arguments. jpayne@69: ** The first argument is an integer which is 0 to disable FK enforcement, jpayne@69: ** positive to enable FK enforcement or negative to leave FK enforcement jpayne@69: ** unchanged. The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether FK enforcement is off or on jpayne@69: ** following this call. The second parameter may be a NULL pointer, in jpayne@69: ** which case the FK enforcement setting is not reported back.
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] jpayne@69: **
SQLITE_DBCONFIG_ENABLE_TRIGGER
jpayne@69: **
^This option is used to enable or disable [CREATE TRIGGER | triggers]. jpayne@69: ** There should be two additional arguments. jpayne@69: ** The first argument is an integer which is 0 to disable triggers, jpayne@69: ** positive to enable triggers or negative to leave the setting unchanged. jpayne@69: ** The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether triggers are disabled or enabled jpayne@69: ** following this call. The second parameter may be a NULL pointer, in jpayne@69: ** which case the trigger setting is not reported back. jpayne@69: ** jpayne@69: **

Originally this option disabled all triggers. ^(However, since jpayne@69: ** SQLite version 3.35.0, TEMP triggers are still allowed even if jpayne@69: ** this option is off. So, in other words, this option now only disables jpayne@69: ** triggers in the main database schema or in the schemas of ATTACH-ed jpayne@69: ** databases.)^

jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] jpayne@69: **
SQLITE_DBCONFIG_ENABLE_VIEW
jpayne@69: **
^This option is used to enable or disable [CREATE VIEW | views]. jpayne@69: ** There should be two additional arguments. jpayne@69: ** The first argument is an integer which is 0 to disable views, jpayne@69: ** positive to enable views or negative to leave the setting unchanged. jpayne@69: ** The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether views are disabled or enabled jpayne@69: ** following this call. The second parameter may be a NULL pointer, in jpayne@69: ** which case the view setting is not reported back. jpayne@69: ** jpayne@69: **

Originally this option disabled all views. ^(However, since jpayne@69: ** SQLite version 3.35.0, TEMP views are still allowed even if jpayne@69: ** this option is off. So, in other words, this option now only disables jpayne@69: ** views in the main database schema or in the schemas of ATTACH-ed jpayne@69: ** databases.)^

jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] jpayne@69: **
SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER
jpayne@69: **
^This option is used to enable or disable the jpayne@69: ** [fts3_tokenizer()] function which is part of the jpayne@69: ** [FTS3] full-text search engine extension. jpayne@69: ** There should be two additional arguments. jpayne@69: ** The first argument is an integer which is 0 to disable fts3_tokenizer() or jpayne@69: ** positive to enable fts3_tokenizer() or negative to leave the setting jpayne@69: ** unchanged. jpayne@69: ** The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled jpayne@69: ** following this call. The second parameter may be a NULL pointer, in jpayne@69: ** which case the new setting is not reported back.
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] jpayne@69: **
SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION
jpayne@69: **
^This option is used to enable or disable the [sqlite3_load_extension()] jpayne@69: ** interface independently of the [load_extension()] SQL function. jpayne@69: ** The [sqlite3_enable_load_extension()] API enables or disables both the jpayne@69: ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. jpayne@69: ** There should be two additional arguments. jpayne@69: ** When the first argument to this interface is 1, then only the C-API is jpayne@69: ** enabled and the SQL function remains disabled. If the first argument to jpayne@69: ** this interface is 0, then both the C-API and the SQL function are disabled. jpayne@69: ** If the first argument is -1, then no changes are made to state of either the jpayne@69: ** C-API or the SQL function. jpayne@69: ** The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface jpayne@69: ** is disabled or enabled following this call. The second parameter may jpayne@69: ** be a NULL pointer, in which case the new setting is not reported back. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_MAINDBNAME]]
SQLITE_DBCONFIG_MAINDBNAME
jpayne@69: **
^This option is used to change the name of the "main" database jpayne@69: ** schema. ^The sole argument is a pointer to a constant UTF8 string jpayne@69: ** which will become the new schema name in place of "main". ^SQLite jpayne@69: ** does not make a copy of the new main schema name string, so the application jpayne@69: ** must ensure that the argument passed into this DBCONFIG option is unchanged jpayne@69: ** until after the database connection closes. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] jpayne@69: **
SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE
jpayne@69: **
Usually, when a database in wal mode is closed or detached from a jpayne@69: ** database handle, SQLite checks if this will mean that there are now no jpayne@69: ** connections at all to the database. If so, it performs a checkpoint jpayne@69: ** operation before closing the connection. This option may be used to jpayne@69: ** override this behavior. The first parameter passed to this operation jpayne@69: ** is an integer - positive to disable checkpoints-on-close, or zero (the jpayne@69: ** default) to enable them, and negative to leave the setting unchanged. jpayne@69: ** The second parameter is a pointer to an integer jpayne@69: ** into which is written 0 or 1 to indicate whether checkpoints-on-close jpayne@69: ** have been disabled - 0 if they are not disabled, 1 if they are. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_ENABLE_QPSG]]
SQLITE_DBCONFIG_ENABLE_QPSG
jpayne@69: **
^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates jpayne@69: ** the [query planner stability guarantee] (QPSG). When the QPSG is active, jpayne@69: ** a single SQL query statement will always use the same algorithm regardless jpayne@69: ** of values of [bound parameters].)^ The QPSG disables some query optimizations jpayne@69: ** that look at the values of bound parameters, which can make some queries jpayne@69: ** slower. But the QPSG has the advantage of more predictable behavior. With jpayne@69: ** the QPSG active, SQLite will always use the same query plan in the field as jpayne@69: ** was used during testing in the lab. jpayne@69: ** The first argument to this setting is an integer which is 0 to disable jpayne@69: ** the QPSG, positive to enable QPSG, or negative to leave the setting jpayne@69: ** unchanged. The second parameter is a pointer to an integer into which jpayne@69: ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled jpayne@69: ** following this call. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_TRIGGER_EQP]]
SQLITE_DBCONFIG_TRIGGER_EQP
jpayne@69: **
By default, the output of EXPLAIN QUERY PLAN commands does not jpayne@69: ** include output for any operations performed by trigger programs. This jpayne@69: ** option is used to set or clear (the default) a flag that governs this jpayne@69: ** behavior. The first parameter passed to this operation is an integer - jpayne@69: ** positive to enable output for trigger programs, or zero to disable it, jpayne@69: ** or negative to leave the setting unchanged. jpayne@69: ** The second parameter is a pointer to an integer into which is written jpayne@69: ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if jpayne@69: ** it is not disabled, 1 if it is. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_RESET_DATABASE]]
SQLITE_DBCONFIG_RESET_DATABASE
jpayne@69: **
Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run jpayne@69: ** [VACUUM] in order to reset a database back to an empty database jpayne@69: ** with no schema and no content. The following process works even for jpayne@69: ** a badly corrupted database file: jpayne@69: **
    jpayne@69: **
  1. If the database connection is newly opened, make sure it has read the jpayne@69: ** database schema by preparing then discarding some query against the jpayne@69: ** database, or calling sqlite3_table_column_metadata(), ignoring any jpayne@69: ** errors. This step is only necessary if the application desires to keep jpayne@69: ** the database in WAL mode after the reset if it was in WAL mode before jpayne@69: ** the reset. jpayne@69: **
  2. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); jpayne@69: **
  3. [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); jpayne@69: **
  4. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); jpayne@69: **
jpayne@69: ** Because resetting a database is destructive and irreversible, the jpayne@69: ** process requires the use of this obscure API and multiple steps to jpayne@69: ** help ensure that it does not happen by accident. Because this jpayne@69: ** feature must be capable of resetting corrupt databases, and jpayne@69: ** shutting down virtual tables may require access to that corrupt jpayne@69: ** storage, the library must abandon any installed virtual tables jpayne@69: ** without calling their xDestroy() methods. jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_DEFENSIVE]]
SQLITE_DBCONFIG_DEFENSIVE
jpayne@69: **
The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the jpayne@69: ** "defensive" flag for a database connection. When the defensive jpayne@69: ** flag is enabled, language features that allow ordinary SQL to jpayne@69: ** deliberately corrupt the database file are disabled. The disabled jpayne@69: ** features include but are not limited to the following: jpayne@69: **
    jpayne@69: **
  • The [PRAGMA writable_schema=ON] statement. jpayne@69: **
  • The [PRAGMA journal_mode=OFF] statement. jpayne@69: **
  • The [PRAGMA schema_version=N] statement. jpayne@69: **
  • Writes to the [sqlite_dbpage] virtual table. jpayne@69: **
  • Direct writes to [shadow tables]. jpayne@69: **
jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]]
SQLITE_DBCONFIG_WRITABLE_SCHEMA
jpayne@69: **
The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the jpayne@69: ** "writable_schema" flag. This has the same effect and is logically equivalent jpayne@69: ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. jpayne@69: ** The first argument to this setting is an integer which is 0 to disable jpayne@69: ** the writable_schema, positive to enable writable_schema, or negative to jpayne@69: ** leave the setting unchanged. The second parameter is a pointer to an jpayne@69: ** integer into which is written 0 or 1 to indicate whether the writable_schema jpayne@69: ** is enabled or disabled following this call. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] jpayne@69: **
SQLITE_DBCONFIG_LEGACY_ALTER_TABLE
jpayne@69: **
The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates jpayne@69: ** the legacy behavior of the [ALTER TABLE RENAME] command such it jpayne@69: ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the jpayne@69: ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for jpayne@69: ** additional information. This feature can also be turned on and off jpayne@69: ** using the [PRAGMA legacy_alter_table] statement. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_DQS_DML]] jpayne@69: **
SQLITE_DBCONFIG_DQS_DML
jpayne@69: **
The SQLITE_DBCONFIG_DQS_DML option activates or deactivates jpayne@69: ** the legacy [double-quoted string literal] misfeature for DML statements jpayne@69: ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The jpayne@69: ** default value of this setting is determined by the [-DSQLITE_DQS] jpayne@69: ** compile-time option. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_DQS_DDL]] jpayne@69: **
SQLITE_DBCONFIG_DQS_DDL
jpayne@69: **
The SQLITE_DBCONFIG_DQS option activates or deactivates jpayne@69: ** the legacy [double-quoted string literal] misfeature for DDL statements, jpayne@69: ** such as CREATE TABLE and CREATE INDEX. The jpayne@69: ** default value of this setting is determined by the [-DSQLITE_DQS] jpayne@69: ** compile-time option. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] jpayne@69: **
SQLITE_DBCONFIG_TRUSTED_SCHEMA
jpayne@69: **
The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to jpayne@69: ** assume that database schemas are untainted by malicious content. jpayne@69: ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite jpayne@69: ** takes additional defensive steps to protect the application from harm jpayne@69: ** including: jpayne@69: **
    jpayne@69: **
  • Prohibit the use of SQL functions inside triggers, views, jpayne@69: ** CHECK constraints, DEFAULT clauses, expression indexes, jpayne@69: ** partial indexes, or generated columns jpayne@69: ** unless those functions are tagged with [SQLITE_INNOCUOUS]. jpayne@69: **
  • Prohibit the use of virtual tables inside of triggers or views jpayne@69: ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. jpayne@69: **
jpayne@69: ** This setting defaults to "on" for legacy compatibility, however jpayne@69: ** all applications are advised to turn it off if possible. This setting jpayne@69: ** can also be controlled using the [PRAGMA trusted_schema] statement. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] jpayne@69: **
SQLITE_DBCONFIG_LEGACY_FILE_FORMAT
jpayne@69: **
The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates jpayne@69: ** the legacy file format flag. When activated, this flag causes all newly jpayne@69: ** created database file to have a schema format version number (the 4-byte jpayne@69: ** integer found at offset 44 into the database header) of 1. This in turn jpayne@69: ** means that the resulting database file will be readable and writable by jpayne@69: ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, jpayne@69: ** newly created databases are generally not understandable by SQLite versions jpayne@69: ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there jpayne@69: ** is now scarcely any need to generate database files that are compatible jpayne@69: ** all the way back to version 3.0.0, and so this setting is of little jpayne@69: ** practical use, but is provided so that SQLite can continue to claim the jpayne@69: ** ability to generate new database files that are compatible with version jpayne@69: ** 3.0.0. jpayne@69: **

Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, jpayne@69: ** the [VACUUM] command will fail with an obscure error when attempting to jpayne@69: ** process a table with generated columns and a descending index. This is jpayne@69: ** not considered a bug since SQLite versions 3.3.0 and earlier do not support jpayne@69: ** either generated columns or descending indexes. jpayne@69: **

jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]] jpayne@69: **
SQLITE_DBCONFIG_STMT_SCANSTATUS
jpayne@69: **
The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in jpayne@69: ** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears jpayne@69: ** a flag that enables collection of the sqlite3_stmt_scanstatus_v2() jpayne@69: ** statistics. For statistics to be collected, the flag must be set on jpayne@69: ** the database handle both when the SQL statement is prepared and when it jpayne@69: ** is stepped. The flag is set (collection of statistics is enabled) jpayne@69: ** by default. This option takes two arguments: an integer and a pointer to jpayne@69: ** an integer.. The first argument is 1, 0, or -1 to enable, disable, or jpayne@69: ** leave unchanged the statement scanstatus option. If the second argument jpayne@69: ** is not NULL, then the value of the statement scanstatus setting after jpayne@69: ** processing the first argument is written into the integer that the second jpayne@69: ** argument points to. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]] jpayne@69: **
SQLITE_DBCONFIG_REVERSE_SCANORDER
jpayne@69: **
The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order jpayne@69: ** in which tables and indexes are scanned so that the scans start at the end jpayne@69: ** and work toward the beginning rather than starting at the beginning and jpayne@69: ** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the jpayne@69: ** same as setting [PRAGMA reverse_unordered_selects]. This option takes jpayne@69: ** two arguments which are an integer and a pointer to an integer. The first jpayne@69: ** argument is 1, 0, or -1 to enable, disable, or leave unchanged the jpayne@69: ** reverse scan order flag, respectively. If the second argument is not NULL, jpayne@69: ** then 0 or 1 is written into the integer that the second argument points to jpayne@69: ** depending on if the reverse scan order flag is set after processing the jpayne@69: ** first argument. jpayne@69: **
jpayne@69: ** jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ jpayne@69: #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */ jpayne@69: #define SQLITE_DBCONFIG_MAX 1019 /* Largest DBCONFIG */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Enable Or Disable Extended Result Codes jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_extended_result_codes() routine enables or disables the jpayne@69: ** [extended result codes] feature of SQLite. ^The extended result jpayne@69: ** codes are disabled by default for historical compatibility. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Last Insert Rowid jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) jpayne@69: ** has a unique 64-bit signed jpayne@69: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available jpayne@69: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those jpayne@69: ** names are not also used by explicitly declared columns. ^If jpayne@69: ** the table has a column of type [INTEGER PRIMARY KEY] then that column jpayne@69: ** is another alias for the rowid. jpayne@69: ** jpayne@69: ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of jpayne@69: ** the most recent successful [INSERT] into a rowid table or [virtual table] jpayne@69: ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not jpayne@69: ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred jpayne@69: ** on the database connection D, then sqlite3_last_insert_rowid(D) returns jpayne@69: ** zero. jpayne@69: ** jpayne@69: ** As well as being set automatically as rows are inserted into database jpayne@69: ** tables, the value returned by this function may be set explicitly by jpayne@69: ** [sqlite3_set_last_insert_rowid()] jpayne@69: ** jpayne@69: ** Some virtual table implementations may INSERT rows into rowid tables as jpayne@69: ** part of committing a transaction (e.g. to flush data accumulated in memory jpayne@69: ** to disk). In this case subsequent calls to this function return the rowid jpayne@69: ** associated with these internal INSERT operations, which leads to jpayne@69: ** unintuitive results. Virtual table implementations that do write to rowid jpayne@69: ** tables in this way can avoid this problem by restoring the original jpayne@69: ** rowid value using [sqlite3_set_last_insert_rowid()] before returning jpayne@69: ** control to the user. jpayne@69: ** jpayne@69: ** ^(If an [INSERT] occurs within a trigger then this routine will jpayne@69: ** return the [rowid] of the inserted row as long as the trigger is jpayne@69: ** running. Once the trigger program ends, the value returned jpayne@69: ** by this routine reverts to what it was before the trigger was fired.)^ jpayne@69: ** jpayne@69: ** ^An [INSERT] that fails due to a constraint violation is not a jpayne@69: ** successful [INSERT] and does not change the value returned by this jpayne@69: ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, jpayne@69: ** and INSERT OR ABORT make no changes to the return value of this jpayne@69: ** routine when their insertion fails. ^(When INSERT OR REPLACE jpayne@69: ** encounters a constraint violation, it does not fail. The jpayne@69: ** INSERT continues to completion after deleting rows that caused jpayne@69: ** the constraint problem so INSERT OR REPLACE will always change jpayne@69: ** the return value of this interface.)^ jpayne@69: ** jpayne@69: ** ^For the purposes of this routine, an [INSERT] is considered to jpayne@69: ** be successful even if it is subsequently rolled back. jpayne@69: ** jpayne@69: ** This function is accessible to SQL statements via the jpayne@69: ** [last_insert_rowid() SQL function]. jpayne@69: ** jpayne@69: ** If a separate thread performs a new [INSERT] on the same jpayne@69: ** database connection while the [sqlite3_last_insert_rowid()] jpayne@69: ** function is running and thus changes the last insert [rowid], jpayne@69: ** then the value returned by [sqlite3_last_insert_rowid()] is jpayne@69: ** unpredictable and might not equal either the old or the new jpayne@69: ** last insert [rowid]. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Set the Last Insert Rowid value. jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to jpayne@69: ** set the value returned by calling sqlite3_last_insert_rowid(D) to R jpayne@69: ** without inserting a row into the database. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Count The Number Of Rows Modified jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These functions return the number of rows modified, inserted or jpayne@69: ** deleted by the most recently completed INSERT, UPDATE or DELETE jpayne@69: ** statement on the database connection specified by the only parameter. jpayne@69: ** The two functions are identical except for the type of the return value jpayne@69: ** and that if the number of rows modified by the most recent INSERT, UPDATE jpayne@69: ** or DELETE is greater than the maximum value supported by type "int", then jpayne@69: ** the return value of sqlite3_changes() is undefined. ^Executing any other jpayne@69: ** type of SQL statement does not modify the value returned by these functions. jpayne@69: ** jpayne@69: ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are jpayne@69: ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], jpayne@69: ** [foreign key actions] or [REPLACE] constraint resolution are not counted. jpayne@69: ** jpayne@69: ** Changes to a view that are intercepted by jpayne@69: ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value jpayne@69: ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or jpayne@69: ** DELETE statement run on a view is always zero. Only changes made to real jpayne@69: ** tables are counted. jpayne@69: ** jpayne@69: ** Things are more complicated if the sqlite3_changes() function is jpayne@69: ** executed while a trigger program is running. This may happen if the jpayne@69: ** program uses the [changes() SQL function], or if some other callback jpayne@69: ** function invokes sqlite3_changes() directly. Essentially: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** ^This means that if the changes() SQL function (or similar) is used jpayne@69: ** by the first INSERT, UPDATE or DELETE statement within a trigger, it jpayne@69: ** returns the value as set when the calling statement began executing. jpayne@69: ** ^If it is used by the second or subsequent such statement within a trigger jpayne@69: ** program, the value returned reflects the number of rows modified by the jpayne@69: ** previous INSERT, UPDATE or DELETE statement within the same trigger. jpayne@69: ** jpayne@69: ** If a separate thread makes changes on the same database connection jpayne@69: ** while [sqlite3_changes()] is running then the value returned jpayne@69: ** is unpredictable and not meaningful. jpayne@69: ** jpayne@69: ** See also: jpayne@69: ** jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_changes(sqlite3*); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Total Number Of Rows Modified jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These functions return the total number of rows inserted, modified or jpayne@69: ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed jpayne@69: ** since the database connection was opened, including those executed as jpayne@69: ** part of trigger programs. The two functions are identical except for the jpayne@69: ** type of the return value and that if the number of rows modified by the jpayne@69: ** connection exceeds the maximum value supported by type "int", then jpayne@69: ** the return value of sqlite3_total_changes() is undefined. ^Executing jpayne@69: ** any other type of SQL statement does not affect the value returned by jpayne@69: ** sqlite3_total_changes(). jpayne@69: ** jpayne@69: ** ^Changes made as part of [foreign key actions] are included in the jpayne@69: ** count, but those made as part of REPLACE constraint resolution are jpayne@69: ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers jpayne@69: ** are not counted. jpayne@69: ** jpayne@69: ** The [sqlite3_total_changes(D)] interface only reports the number jpayne@69: ** of rows that changed due to SQL statement run against database jpayne@69: ** connection D. Any changes by other database connections are ignored. jpayne@69: ** To detect changes against a database file from other database jpayne@69: ** connections use the [PRAGMA data_version] command or the jpayne@69: ** [SQLITE_FCNTL_DATA_VERSION] [file control]. jpayne@69: ** jpayne@69: ** If a separate thread makes changes on the same database connection jpayne@69: ** while [sqlite3_total_changes()] is running then the value jpayne@69: ** returned is unpredictable and not meaningful. jpayne@69: ** jpayne@69: ** See also: jpayne@69: ** jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_total_changes(sqlite3*); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Interrupt A Long-Running Query jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This function causes any pending database operation to abort and jpayne@69: ** return at its earliest opportunity. This routine is typically jpayne@69: ** called in response to a user action such as pressing "Cancel" jpayne@69: ** or Ctrl-C where the user wants a long query operation to halt jpayne@69: ** immediately. jpayne@69: ** jpayne@69: ** ^It is safe to call this routine from a thread different from the jpayne@69: ** thread that is currently running the database operation. But it jpayne@69: ** is not safe to call this routine with a [database connection] that jpayne@69: ** is closed or might close before sqlite3_interrupt() returns. jpayne@69: ** jpayne@69: ** ^If an SQL operation is very nearly finished at the time when jpayne@69: ** sqlite3_interrupt() is called, then it might not have an opportunity jpayne@69: ** to be interrupted and might continue to completion. jpayne@69: ** jpayne@69: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. jpayne@69: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE jpayne@69: ** that is inside an explicit transaction, then the entire transaction jpayne@69: ** will be rolled back automatically. jpayne@69: ** jpayne@69: ** ^The sqlite3_interrupt(D) call is in effect until all currently running jpayne@69: ** SQL statements on [database connection] D complete. ^Any new SQL statements jpayne@69: ** that are started after the sqlite3_interrupt() call and before the jpayne@69: ** running statement count reaches zero are interrupted as if they had been jpayne@69: ** running prior to the sqlite3_interrupt() call. ^New SQL statements jpayne@69: ** that are started after the running statement count reaches zero are jpayne@69: ** not effected by the sqlite3_interrupt(). jpayne@69: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running jpayne@69: ** SQL statements is a no-op and has no effect on SQL statements jpayne@69: ** that are started after the sqlite3_interrupt() call returns. jpayne@69: ** jpayne@69: ** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether jpayne@69: ** or not an interrupt is currently in effect for [database connection] D. jpayne@69: ** It returns 1 if an interrupt is currently in effect, or 0 otherwise. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_interrupt(sqlite3*); jpayne@69: SQLITE_API int sqlite3_is_interrupted(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine If An SQL Statement Is Complete jpayne@69: ** jpayne@69: ** These routines are useful during command-line input to determine if the jpayne@69: ** currently entered text seems to form a complete SQL statement or jpayne@69: ** if additional input is needed before sending the text into jpayne@69: ** SQLite for parsing. ^These routines return 1 if the input string jpayne@69: ** appears to be a complete SQL statement. ^A statement is judged to be jpayne@69: ** complete if it ends with a semicolon token and is not a prefix of a jpayne@69: ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within jpayne@69: ** string literals or quoted identifier names or comments are not jpayne@69: ** independent tokens (they are part of the token in which they are jpayne@69: ** embedded) and thus do not count as a statement terminator. ^Whitespace jpayne@69: ** and comments that follow the final semicolon are ignored. jpayne@69: ** jpayne@69: ** ^These routines return 0 if the statement is incomplete. ^If a jpayne@69: ** memory allocation fails, then SQLITE_NOMEM is returned. jpayne@69: ** jpayne@69: ** ^These routines do not parse the SQL statements thus jpayne@69: ** will not detect syntactically incorrect SQL. jpayne@69: ** jpayne@69: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior jpayne@69: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked jpayne@69: ** automatically by sqlite3_complete16(). If that initialization fails, jpayne@69: ** then the return value from sqlite3_complete16() will be non-zero jpayne@69: ** regardless of whether or not the input SQL is complete.)^ jpayne@69: ** jpayne@69: ** The input to [sqlite3_complete()] must be a zero-terminated jpayne@69: ** UTF-8 string. jpayne@69: ** jpayne@69: ** The input to [sqlite3_complete16()] must be a zero-terminated jpayne@69: ** UTF-16 string in native byte order. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_complete(const char *sql); jpayne@69: SQLITE_API int sqlite3_complete16(const void *sql); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors jpayne@69: ** KEYWORDS: {busy-handler callback} {busy handler} jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X jpayne@69: ** that might be invoked with argument P whenever jpayne@69: ** an attempt is made to access a database table associated with jpayne@69: ** [database connection] D when another thread jpayne@69: ** or process has the table locked. jpayne@69: ** The sqlite3_busy_handler() interface is used to implement jpayne@69: ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. jpayne@69: ** jpayne@69: ** ^If the busy callback is NULL, then [SQLITE_BUSY] jpayne@69: ** is returned immediately upon encountering the lock. ^If the busy callback jpayne@69: ** is not NULL, then the callback might be invoked with two arguments. jpayne@69: ** jpayne@69: ** ^The first argument to the busy handler is a copy of the void* pointer which jpayne@69: ** is the third argument to sqlite3_busy_handler(). ^The second argument to jpayne@69: ** the busy handler callback is the number of times that the busy handler has jpayne@69: ** been invoked previously for the same locking event. ^If the jpayne@69: ** busy callback returns 0, then no additional attempts are made to jpayne@69: ** access the database and [SQLITE_BUSY] is returned jpayne@69: ** to the application. jpayne@69: ** ^If the callback returns non-zero, then another attempt jpayne@69: ** is made to access the database and the cycle repeats. jpayne@69: ** jpayne@69: ** The presence of a busy handler does not guarantee that it will be invoked jpayne@69: ** when there is lock contention. ^If SQLite determines that invoking the busy jpayne@69: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] jpayne@69: ** to the application instead of invoking the jpayne@69: ** busy handler. jpayne@69: ** Consider a scenario where one process is holding a read lock that jpayne@69: ** it is trying to promote to a reserved lock and jpayne@69: ** a second process is holding a reserved lock that it is trying jpayne@69: ** to promote to an exclusive lock. The first process cannot proceed jpayne@69: ** because it is blocked by the second and the second process cannot jpayne@69: ** proceed because it is blocked by the first. If both processes jpayne@69: ** invoke the busy handlers, neither will make any progress. Therefore, jpayne@69: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this jpayne@69: ** will induce the first process to release its read lock and allow jpayne@69: ** the second process to proceed. jpayne@69: ** jpayne@69: ** ^The default busy callback is NULL. jpayne@69: ** jpayne@69: ** ^(There can only be a single busy handler defined for each jpayne@69: ** [database connection]. Setting a new busy handler clears any jpayne@69: ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] jpayne@69: ** or evaluating [PRAGMA busy_timeout=N] will change the jpayne@69: ** busy handler and thus clear any previously set busy handler. jpayne@69: ** jpayne@69: ** The busy callback should not take any actions which modify the jpayne@69: ** database connection that invoked the busy handler. In other words, jpayne@69: ** the busy handler is not reentrant. Any such actions jpayne@69: ** result in undefined behavior. jpayne@69: ** jpayne@69: ** A busy handler must not close the database connection jpayne@69: ** or [prepared statement] that invoked the busy handler. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Set A Busy Timeout jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps jpayne@69: ** for a specified amount of time when a table is locked. ^The handler jpayne@69: ** will sleep multiple times until at least "ms" milliseconds of sleeping jpayne@69: ** have accumulated. ^After at least "ms" milliseconds of sleeping, jpayne@69: ** the handler returns 0 which causes [sqlite3_step()] to return jpayne@69: ** [SQLITE_BUSY]. jpayne@69: ** jpayne@69: ** ^Calling this routine with an argument less than or equal to zero jpayne@69: ** turns off all busy handlers. jpayne@69: ** jpayne@69: ** ^(There can only be a single busy handler for a particular jpayne@69: ** [database connection] at any given moment. If another busy handler jpayne@69: ** was defined (using [sqlite3_busy_handler()]) prior to calling jpayne@69: ** this routine, that other busy handler is cleared.)^ jpayne@69: ** jpayne@69: ** See also: [PRAGMA busy_timeout] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Convenience Routines For Running Queries jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** This is a legacy interface that is preserved for backwards compatibility. jpayne@69: ** Use of this interface is not recommended. jpayne@69: ** jpayne@69: ** Definition: A result table is memory data structure created by the jpayne@69: ** [sqlite3_get_table()] interface. A result table records the jpayne@69: ** complete query results from one or more queries. jpayne@69: ** jpayne@69: ** The table conceptually has a number of rows and columns. But jpayne@69: ** these numbers are not part of the result table itself. These jpayne@69: ** numbers are obtained separately. Let N be the number of rows jpayne@69: ** and M be the number of columns. jpayne@69: ** jpayne@69: ** A result table is an array of pointers to zero-terminated UTF-8 strings. jpayne@69: ** There are (N+1)*M elements in the array. The first M pointers point jpayne@69: ** to zero-terminated strings that contain the names of the columns. jpayne@69: ** The remaining entries all point to query results. NULL values result jpayne@69: ** in NULL pointers. All other values are in their UTF-8 zero-terminated jpayne@69: ** string representation as returned by [sqlite3_column_text()]. jpayne@69: ** jpayne@69: ** A result table might consist of one or more memory allocations. jpayne@69: ** It is not safe to pass a result table directly to [sqlite3_free()]. jpayne@69: ** A result table should be deallocated using [sqlite3_free_table()]. jpayne@69: ** jpayne@69: ** ^(As an example of the result table format, suppose a query result jpayne@69: ** is as follows: jpayne@69: ** jpayne@69: ** 
jpayne@69: **        Name        | Age
jpayne@69: **        -----------------------
jpayne@69: **        Alice       | 43
jpayne@69: **        Bob         | 28
jpayne@69: **        Cindy       | 21
jpayne@69: **
jpayne@69: ** jpayne@69: ** There are two columns (M==2) and three rows (N==3). Thus the jpayne@69: ** result table has 8 entries. Suppose the result table is stored jpayne@69: ** in an array named azResult. Then azResult holds this content: jpayne@69: ** jpayne@69: ** 
jpayne@69: **        azResult[0] = "Name";
jpayne@69: **        azResult[1] = "Age";
jpayne@69: **        azResult[2] = "Alice";
jpayne@69: **        azResult[3] = "43";
jpayne@69: **        azResult[4] = "Bob";
jpayne@69: **        azResult[5] = "28";
jpayne@69: **        azResult[6] = "Cindy";
jpayne@69: **        azResult[7] = "21";
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_get_table() function evaluates one or more jpayne@69: ** semicolon-separated SQL statements in the zero-terminated UTF-8 jpayne@69: ** string of its 2nd parameter and returns a result table to the jpayne@69: ** pointer given in its 3rd parameter. jpayne@69: ** jpayne@69: ** After the application has finished with the result from sqlite3_get_table(), jpayne@69: ** it must pass the result table pointer to sqlite3_free_table() in order to jpayne@69: ** release the memory that was malloced. Because of the way the jpayne@69: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling jpayne@69: ** function must not try to call [sqlite3_free()] directly. Only jpayne@69: ** [sqlite3_free_table()] is able to release the memory properly and safely. jpayne@69: ** jpayne@69: ** The sqlite3_get_table() interface is implemented as a wrapper around jpayne@69: ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access jpayne@69: ** to any internal data structures of SQLite. It uses only the public jpayne@69: ** interface defined here. As a consequence, errors that occur in the jpayne@69: ** wrapper layer outside of the internal [sqlite3_exec()] call are not jpayne@69: ** reflected in subsequent calls to [sqlite3_errcode()] or jpayne@69: ** [sqlite3_errmsg()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_get_table( jpayne@69: sqlite3 *db, /* An open database */ jpayne@69: const char *zSql, /* SQL to be evaluated */ jpayne@69: char ***pazResult, /* Results of the query */ jpayne@69: int *pnRow, /* Number of result rows written here */ jpayne@69: int *pnColumn, /* Number of result columns written here */ jpayne@69: char **pzErrmsg /* Error msg written here */ jpayne@69: ); jpayne@69: SQLITE_API void sqlite3_free_table(char **result); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Formatted String Printing Functions jpayne@69: ** jpayne@69: ** These routines are work-alikes of the "printf()" family of functions jpayne@69: ** from the standard C library. jpayne@69: ** These routines understand most of the common formatting options from jpayne@69: ** the standard library printf() jpayne@69: ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). jpayne@69: ** See the [built-in printf()] documentation for details. jpayne@69: ** jpayne@69: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their jpayne@69: ** results into memory obtained from [sqlite3_malloc64()]. jpayne@69: ** The strings returned by these two routines should be jpayne@69: ** released by [sqlite3_free()]. ^Both routines return a jpayne@69: ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough jpayne@69: ** memory to hold the resulting string. jpayne@69: ** jpayne@69: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from jpayne@69: ** the standard C library. The result is written into the jpayne@69: ** buffer supplied as the second parameter whose size is given by jpayne@69: ** the first parameter. Note that the order of the jpayne@69: ** first two parameters is reversed from snprintf().)^ This is an jpayne@69: ** historical accident that cannot be fixed without breaking jpayne@69: ** backwards compatibility. ^(Note also that sqlite3_snprintf() jpayne@69: ** returns a pointer to its buffer instead of the number of jpayne@69: ** characters actually written into the buffer.)^ We admit that jpayne@69: ** the number of characters written would be a more useful return jpayne@69: ** value but we cannot change the implementation of sqlite3_snprintf() jpayne@69: ** now without breaking compatibility. jpayne@69: ** jpayne@69: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() jpayne@69: ** guarantees that the buffer is always zero-terminated. ^The first jpayne@69: ** parameter "n" is the total size of the buffer, including space for jpayne@69: ** the zero terminator. So the longest string that can be completely jpayne@69: ** written will be n-1 characters. jpayne@69: ** jpayne@69: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). jpayne@69: ** jpayne@69: ** See also: [built-in printf()], [printf() SQL function] jpayne@69: */ jpayne@69: SQLITE_API char *sqlite3_mprintf(const char*,...); jpayne@69: SQLITE_API char *sqlite3_vmprintf(const char*, va_list); jpayne@69: SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); jpayne@69: SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Memory Allocation Subsystem jpayne@69: ** jpayne@69: ** The SQLite core uses these three routines for all of its own jpayne@69: ** internal memory allocation needs. "Core" in the previous sentence jpayne@69: ** does not include operating-system specific [VFS] implementation. The jpayne@69: ** Windows VFS uses native malloc() and free() for some operations. jpayne@69: ** jpayne@69: ** ^The sqlite3_malloc() routine returns a pointer to a block jpayne@69: ** of memory at least N bytes in length, where N is the parameter. jpayne@69: ** ^If sqlite3_malloc() is unable to obtain sufficient free jpayne@69: ** memory, it returns a NULL pointer. ^If the parameter N to jpayne@69: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns jpayne@69: ** a NULL pointer. jpayne@69: ** jpayne@69: ** ^The sqlite3_malloc64(N) routine works just like jpayne@69: ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead jpayne@69: ** of a signed 32-bit integer. jpayne@69: ** jpayne@69: ** ^Calling sqlite3_free() with a pointer previously returned jpayne@69: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so jpayne@69: ** that it might be reused. ^The sqlite3_free() routine is jpayne@69: ** a no-op if is called with a NULL pointer. Passing a NULL pointer jpayne@69: ** to sqlite3_free() is harmless. After being freed, memory jpayne@69: ** should neither be read nor written. Even reading previously freed jpayne@69: ** memory might result in a segmentation fault or other severe error. jpayne@69: ** Memory corruption, a segmentation fault, or other severe error jpayne@69: ** might result if sqlite3_free() is called with a non-NULL pointer that jpayne@69: ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). jpayne@69: ** jpayne@69: ** ^The sqlite3_realloc(X,N) interface attempts to resize a jpayne@69: ** prior memory allocation X to be at least N bytes. jpayne@69: ** ^If the X parameter to sqlite3_realloc(X,N) jpayne@69: ** is a NULL pointer then its behavior is identical to calling jpayne@69: ** sqlite3_malloc(N). jpayne@69: ** ^If the N parameter to sqlite3_realloc(X,N) is zero or jpayne@69: ** negative then the behavior is exactly the same as calling jpayne@69: ** sqlite3_free(X). jpayne@69: ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation jpayne@69: ** of at least N bytes in size or NULL if insufficient memory is available. jpayne@69: ** ^If M is the size of the prior allocation, then min(N,M) bytes jpayne@69: ** of the prior allocation are copied into the beginning of buffer returned jpayne@69: ** by sqlite3_realloc(X,N) and the prior allocation is freed. jpayne@69: ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the jpayne@69: ** prior allocation is not freed. jpayne@69: ** jpayne@69: ** ^The sqlite3_realloc64(X,N) interfaces works the same as jpayne@69: ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead jpayne@69: ** of a 32-bit signed integer. jpayne@69: ** jpayne@69: ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), jpayne@69: ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then jpayne@69: ** sqlite3_msize(X) returns the size of that memory allocation in bytes. jpayne@69: ** ^The value returned by sqlite3_msize(X) might be larger than the number jpayne@69: ** of bytes requested when X was allocated. ^If X is a NULL pointer then jpayne@69: ** sqlite3_msize(X) returns zero. If X points to something that is not jpayne@69: ** the beginning of memory allocation, or if it points to a formerly jpayne@69: ** valid memory allocation that has now been freed, then the behavior jpayne@69: ** of sqlite3_msize(X) is undefined and possibly harmful. jpayne@69: ** jpayne@69: ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), jpayne@69: ** sqlite3_malloc64(), and sqlite3_realloc64() jpayne@69: ** is always aligned to at least an 8 byte boundary, or to a jpayne@69: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time jpayne@69: ** option is used. jpayne@69: ** jpayne@69: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] jpayne@69: ** must be either NULL or else pointers obtained from a prior jpayne@69: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have jpayne@69: ** not yet been released. jpayne@69: ** jpayne@69: ** The application must not read or write any part of jpayne@69: ** a block of memory after it has been released using jpayne@69: ** [sqlite3_free()] or [sqlite3_realloc()]. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_malloc(int); jpayne@69: SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); jpayne@69: SQLITE_API void *sqlite3_realloc(void*, int); jpayne@69: SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); jpayne@69: SQLITE_API void sqlite3_free(void*); jpayne@69: SQLITE_API sqlite3_uint64 sqlite3_msize(void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Memory Allocator Statistics jpayne@69: ** jpayne@69: ** SQLite provides these two interfaces for reporting on the status jpayne@69: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] jpayne@69: ** routines, which form the built-in memory allocation subsystem. jpayne@69: ** jpayne@69: ** ^The [sqlite3_memory_used()] routine returns the number of bytes jpayne@69: ** of memory currently outstanding (malloced but not freed). jpayne@69: ** ^The [sqlite3_memory_highwater()] routine returns the maximum jpayne@69: ** value of [sqlite3_memory_used()] since the high-water mark jpayne@69: ** was last reset. ^The values returned by [sqlite3_memory_used()] and jpayne@69: ** [sqlite3_memory_highwater()] include any overhead jpayne@69: ** added by SQLite in its implementation of [sqlite3_malloc()], jpayne@69: ** but not overhead added by the any underlying system library jpayne@69: ** routines that [sqlite3_malloc()] may call. jpayne@69: ** jpayne@69: ** ^The memory high-water mark is reset to the current value of jpayne@69: ** [sqlite3_memory_used()] if and only if the parameter to jpayne@69: ** [sqlite3_memory_highwater()] is true. ^The value returned jpayne@69: ** by [sqlite3_memory_highwater(1)] is the high-water mark jpayne@69: ** prior to the reset. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_int64 sqlite3_memory_used(void); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Pseudo-Random Number Generator jpayne@69: ** jpayne@69: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to jpayne@69: ** select random [ROWID | ROWIDs] when inserting new records into a table that jpayne@69: ** already uses the largest possible [ROWID]. The PRNG is also used for jpayne@69: ** the built-in random() and randomblob() SQL functions. This interface allows jpayne@69: ** applications to access the same PRNG for other purposes. jpayne@69: ** jpayne@69: ** ^A call to this routine stores N bytes of randomness into buffer P. jpayne@69: ** ^The P parameter can be a NULL pointer. jpayne@69: ** jpayne@69: ** ^If this routine has not been previously called or if the previous jpayne@69: ** call had N less than one or a NULL pointer for P, then the PRNG is jpayne@69: ** seeded using randomness obtained from the xRandomness method of jpayne@69: ** the default [sqlite3_vfs] object. jpayne@69: ** ^If the previous call to this routine had an N of 1 or more and a jpayne@69: ** non-NULL P then the pseudo-randomness is generated jpayne@69: ** internally and without recourse to the [sqlite3_vfs] xRandomness jpayne@69: ** method. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_randomness(int N, void *P); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Compile-Time Authorization Callbacks jpayne@69: ** METHOD: sqlite3 jpayne@69: ** KEYWORDS: {authorizer callback} jpayne@69: ** jpayne@69: ** ^This routine registers an authorizer callback with a particular jpayne@69: ** [database connection], supplied in the first argument. jpayne@69: ** ^The authorizer callback is invoked as SQL statements are being compiled jpayne@69: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], jpayne@69: ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], jpayne@69: ** and [sqlite3_prepare16_v3()]. ^At various jpayne@69: ** points during the compilation process, as logic is being created jpayne@69: ** to perform various actions, the authorizer callback is invoked to jpayne@69: ** see if those actions are allowed. ^The authorizer callback should jpayne@69: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the jpayne@69: ** specific action but allow the SQL statement to continue to be jpayne@69: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be jpayne@69: ** rejected with an error. ^If the authorizer callback returns jpayne@69: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] jpayne@69: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered jpayne@69: ** the authorizer will fail with an error message. jpayne@69: ** jpayne@69: ** When the callback returns [SQLITE_OK], that means the operation jpayne@69: ** requested is ok. ^When the callback returns [SQLITE_DENY], the jpayne@69: ** [sqlite3_prepare_v2()] or equivalent call that triggered the jpayne@69: ** authorizer will fail with an error message explaining that jpayne@69: ** access is denied. jpayne@69: ** jpayne@69: ** ^The first parameter to the authorizer callback is a copy of the third jpayne@69: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter jpayne@69: ** to the callback is an integer [SQLITE_COPY | action code] that specifies jpayne@69: ** the particular action to be authorized. ^The third through sixth parameters jpayne@69: ** to the callback are either NULL pointers or zero-terminated strings jpayne@69: ** that contain additional details about the action to be authorized. jpayne@69: ** Applications must always be prepared to encounter a NULL pointer in any jpayne@69: ** of the third through the sixth parameters of the authorization callback. jpayne@69: ** jpayne@69: ** ^If the action code is [SQLITE_READ] jpayne@69: ** and the callback returns [SQLITE_IGNORE] then the jpayne@69: ** [prepared statement] statement is constructed to substitute jpayne@69: ** a NULL value in place of the table column that would have jpayne@69: ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] jpayne@69: ** return can be used to deny an untrusted user access to individual jpayne@69: ** columns of a table. jpayne@69: ** ^When a table is referenced by a [SELECT] but no column values are jpayne@69: ** extracted from that table (for example in a query like jpayne@69: ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback jpayne@69: ** is invoked once for that table with a column name that is an empty string. jpayne@69: ** ^If the action code is [SQLITE_DELETE] and the callback returns jpayne@69: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the jpayne@69: ** [truncate optimization] is disabled and all rows are deleted individually. jpayne@69: ** jpayne@69: ** An authorizer is used when [sqlite3_prepare | preparing] jpayne@69: ** SQL statements from an untrusted source, to ensure that the SQL statements jpayne@69: ** do not try to access data they are not allowed to see, or that they do not jpayne@69: ** try to execute malicious statements that damage the database. For jpayne@69: ** example, an application may allow a user to enter arbitrary jpayne@69: ** SQL queries for evaluation by a database. But the application does jpayne@69: ** not want the user to be able to make arbitrary changes to the jpayne@69: ** database. An authorizer could then be put in place while the jpayne@69: ** user-entered SQL is being [sqlite3_prepare | prepared] that jpayne@69: ** disallows everything except [SELECT] statements. jpayne@69: ** jpayne@69: ** Applications that need to process SQL from untrusted sources jpayne@69: ** might also consider lowering resource limits using [sqlite3_limit()] jpayne@69: ** and limiting database size using the [max_page_count] [PRAGMA] jpayne@69: ** in addition to using an authorizer. jpayne@69: ** jpayne@69: ** ^(Only a single authorizer can be in place on a database connection jpayne@69: ** at a time. Each call to sqlite3_set_authorizer overrides the jpayne@69: ** previous call.)^ ^Disable the authorizer by installing a NULL callback. jpayne@69: ** The authorizer is disabled by default. jpayne@69: ** jpayne@69: ** The authorizer callback must not do anything that will modify jpayne@69: ** the database connection that invoked the authorizer callback. jpayne@69: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their jpayne@69: ** database connections for the meaning of "modify" in this paragraph. jpayne@69: ** jpayne@69: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the jpayne@69: ** statement might be re-prepared during [sqlite3_step()] due to a jpayne@69: ** schema change. Hence, the application should ensure that the jpayne@69: ** correct authorizer callback remains in place during the [sqlite3_step()]. jpayne@69: ** jpayne@69: ** ^Note that the authorizer callback is invoked only during jpayne@69: ** [sqlite3_prepare()] or its variants. Authorization is not jpayne@69: ** performed during statement evaluation in [sqlite3_step()], unless jpayne@69: ** as stated in the previous paragraph, sqlite3_step() invokes jpayne@69: ** sqlite3_prepare_v2() to reprepare a statement after a schema change. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_set_authorizer( jpayne@69: sqlite3*, jpayne@69: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), jpayne@69: void *pUserData jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Authorizer Return Codes jpayne@69: ** jpayne@69: ** The [sqlite3_set_authorizer | authorizer callback function] must jpayne@69: ** return either [SQLITE_OK] or one of these two constants in order jpayne@69: ** to signal SQLite whether or not the action is permitted. See the jpayne@69: ** [sqlite3_set_authorizer | authorizer documentation] for additional jpayne@69: ** information. jpayne@69: ** jpayne@69: ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] jpayne@69: ** returned from the [sqlite3_vtab_on_conflict()] interface. jpayne@69: */ jpayne@69: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ jpayne@69: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Authorizer Action Codes jpayne@69: ** jpayne@69: ** The [sqlite3_set_authorizer()] interface registers a callback function jpayne@69: ** that is invoked to authorize certain SQL statement actions. The jpayne@69: ** second parameter to the callback is an integer code that specifies jpayne@69: ** what action is being authorized. These are the integer action codes that jpayne@69: ** the authorizer callback may be passed. jpayne@69: ** jpayne@69: ** These action code values signify what kind of operation is to be jpayne@69: ** authorized. The 3rd and 4th parameters to the authorization jpayne@69: ** callback function will be parameters or NULL depending on which of these jpayne@69: ** codes is used as the second parameter. ^(The 5th parameter to the jpayne@69: ** authorizer callback is the name of the database ("main", "temp", jpayne@69: ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback jpayne@69: ** is the name of the inner-most trigger or view that is responsible for jpayne@69: ** the access attempt or NULL if this access attempt is directly from jpayne@69: ** top-level SQL code. jpayne@69: */ jpayne@69: /******************************************* 3rd ************ 4th ***********/ jpayne@69: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ jpayne@69: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ jpayne@69: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ jpayne@69: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ jpayne@69: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ jpayne@69: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ jpayne@69: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ jpayne@69: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ jpayne@69: #define SQLITE_DELETE 9 /* Table Name NULL */ jpayne@69: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ jpayne@69: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ jpayne@69: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ jpayne@69: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ jpayne@69: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ jpayne@69: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ jpayne@69: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ jpayne@69: #define SQLITE_DROP_VIEW 17 /* View Name NULL */ jpayne@69: #define SQLITE_INSERT 18 /* Table Name NULL */ jpayne@69: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ jpayne@69: #define SQLITE_READ 20 /* Table Name Column Name */ jpayne@69: #define SQLITE_SELECT 21 /* NULL NULL */ jpayne@69: #define SQLITE_TRANSACTION 22 /* Operation NULL */ jpayne@69: #define SQLITE_UPDATE 23 /* Table Name Column Name */ jpayne@69: #define SQLITE_ATTACH 24 /* Filename NULL */ jpayne@69: #define SQLITE_DETACH 25 /* Database Name NULL */ jpayne@69: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ jpayne@69: #define SQLITE_REINDEX 27 /* Index Name NULL */ jpayne@69: #define SQLITE_ANALYZE 28 /* Table Name NULL */ jpayne@69: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ jpayne@69: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ jpayne@69: #define SQLITE_FUNCTION 31 /* NULL Function Name */ jpayne@69: #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ jpayne@69: #define SQLITE_COPY 0 /* No longer used */ jpayne@69: #define SQLITE_RECURSIVE 33 /* NULL NULL */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Deprecated Tracing And Profiling Functions jpayne@69: ** DEPRECATED jpayne@69: ** jpayne@69: ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface jpayne@69: ** instead of the routines described here. jpayne@69: ** jpayne@69: ** These routines register callback functions that can be used for jpayne@69: ** tracing and profiling the execution of SQL statements. jpayne@69: ** jpayne@69: ** ^The callback function registered by sqlite3_trace() is invoked at jpayne@69: ** various times when an SQL statement is being run by [sqlite3_step()]. jpayne@69: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the jpayne@69: ** SQL statement text as the statement first begins executing. jpayne@69: ** ^(Additional sqlite3_trace() callbacks might occur jpayne@69: ** as each triggered subprogram is entered. The callbacks for triggers jpayne@69: ** contain a UTF-8 SQL comment that identifies the trigger.)^ jpayne@69: ** jpayne@69: ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit jpayne@69: ** the length of [bound parameter] expansion in the output of sqlite3_trace(). jpayne@69: ** jpayne@69: ** ^The callback function registered by sqlite3_profile() is invoked jpayne@69: ** as each SQL statement finishes. ^The profile callback contains jpayne@69: ** the original statement text and an estimate of wall-clock time jpayne@69: ** of how long that statement took to run. ^The profile callback jpayne@69: ** time is in units of nanoseconds, however the current implementation jpayne@69: ** is only capable of millisecond resolution so the six least significant jpayne@69: ** digits in the time are meaningless. Future versions of SQLite jpayne@69: ** might provide greater resolution on the profiler callback. Invoking jpayne@69: ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the jpayne@69: ** profile callback. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, jpayne@69: void(*xTrace)(void*,const char*), void*); jpayne@69: SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, jpayne@69: void(*xProfile)(void*,const char*,sqlite3_uint64), void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: SQL Trace Event Codes jpayne@69: ** KEYWORDS: SQLITE_TRACE jpayne@69: ** jpayne@69: ** These constants identify classes of events that can be monitored jpayne@69: ** using the [sqlite3_trace_v2()] tracing logic. The M argument jpayne@69: ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of jpayne@69: ** the following constants. ^The first argument to the trace callback jpayne@69: ** is one of the following constants. jpayne@69: ** jpayne@69: ** New tracing constants may be added in future releases. jpayne@69: ** jpayne@69: ** ^A trace callback has four arguments: xCallback(T,C,P,X). jpayne@69: ** ^The T argument is one of the integer type codes above. jpayne@69: ** ^The C argument is a copy of the context pointer passed in as the jpayne@69: ** fourth argument to [sqlite3_trace_v2()]. jpayne@69: ** The P and X arguments are pointers whose meanings depend on T. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_TRACE_STMT]]
SQLITE_TRACE_STMT
jpayne@69: **
^An SQLITE_TRACE_STMT callback is invoked when a prepared statement jpayne@69: ** first begins running and possibly at other times during the jpayne@69: ** execution of the prepared statement, such as at the start of each jpayne@69: ** trigger subprogram. ^The P argument is a pointer to the jpayne@69: ** [prepared statement]. ^The X argument is a pointer to a string which jpayne@69: ** is the unexpanded SQL text of the prepared statement or an SQL comment jpayne@69: ** that indicates the invocation of a trigger. ^The callback can compute jpayne@69: ** the same text that would have been returned by the legacy [sqlite3_trace()] jpayne@69: ** interface by using the X argument when X begins with "--" and invoking jpayne@69: ** [sqlite3_expanded_sql(P)] otherwise. jpayne@69: ** jpayne@69: ** [[SQLITE_TRACE_PROFILE]]
SQLITE_TRACE_PROFILE
jpayne@69: **
^An SQLITE_TRACE_PROFILE callback provides approximately the same jpayne@69: ** information as is provided by the [sqlite3_profile()] callback. jpayne@69: ** ^The P argument is a pointer to the [prepared statement] and the jpayne@69: ** X argument points to a 64-bit integer which is approximately jpayne@69: ** the number of nanoseconds that the prepared statement took to run. jpayne@69: ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. jpayne@69: ** jpayne@69: ** [[SQLITE_TRACE_ROW]]
SQLITE_TRACE_ROW
jpayne@69: **
^An SQLITE_TRACE_ROW callback is invoked whenever a prepared jpayne@69: ** statement generates a single row of result. jpayne@69: ** ^The P argument is a pointer to the [prepared statement] and the jpayne@69: ** X argument is unused. jpayne@69: ** jpayne@69: ** [[SQLITE_TRACE_CLOSE]]
SQLITE_TRACE_CLOSE
jpayne@69: **
^An SQLITE_TRACE_CLOSE callback is invoked when a database jpayne@69: ** connection closes. jpayne@69: ** ^The P argument is a pointer to the [database connection] object jpayne@69: ** and the X argument is unused. jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_TRACE_STMT 0x01 jpayne@69: #define SQLITE_TRACE_PROFILE 0x02 jpayne@69: #define SQLITE_TRACE_ROW 0x04 jpayne@69: #define SQLITE_TRACE_CLOSE 0x08 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: SQL Trace Hook jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback jpayne@69: ** function X against [database connection] D, using property mask M jpayne@69: ** and context pointer P. ^If the X callback is jpayne@69: ** NULL or if the M mask is zero, then tracing is disabled. The jpayne@69: ** M argument should be the bitwise OR-ed combination of jpayne@69: ** zero or more [SQLITE_TRACE] constants. jpayne@69: ** jpayne@69: ** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P) jpayne@69: ** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or jpayne@69: ** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each jpayne@69: ** database connection may have at most one trace callback. jpayne@69: ** jpayne@69: ** ^The X callback is invoked whenever any of the events identified by jpayne@69: ** mask M occur. ^The integer return value from the callback is currently jpayne@69: ** ignored, though this may change in future releases. Callback jpayne@69: ** implementations should return zero to ensure future compatibility. jpayne@69: ** jpayne@69: ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). jpayne@69: ** ^The T argument is one of the [SQLITE_TRACE] jpayne@69: ** constants to indicate why the callback was invoked. jpayne@69: ** ^The C argument is a copy of the context pointer. jpayne@69: ** The P and X arguments are pointers whose meanings depend on T. jpayne@69: ** jpayne@69: ** The sqlite3_trace_v2() interface is intended to replace the legacy jpayne@69: ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which jpayne@69: ** are deprecated. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_trace_v2( jpayne@69: sqlite3*, jpayne@69: unsigned uMask, jpayne@69: int(*xCallback)(unsigned,void*,void*,void*), jpayne@69: void *pCtx jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Query Progress Callbacks jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback jpayne@69: ** function X to be invoked periodically during long running calls to jpayne@69: ** [sqlite3_step()] and [sqlite3_prepare()] and similar for jpayne@69: ** database connection D. An example use for this jpayne@69: ** interface is to keep a GUI updated during a large query. jpayne@69: ** jpayne@69: ** ^The parameter P is passed through as the only parameter to the jpayne@69: ** callback function X. ^The parameter N is the approximate number of jpayne@69: ** [virtual machine instructions] that are evaluated between successive jpayne@69: ** invocations of the callback X. ^If N is less than one then the progress jpayne@69: ** handler is disabled. jpayne@69: ** jpayne@69: ** ^Only a single progress handler may be defined at one time per jpayne@69: ** [database connection]; setting a new progress handler cancels the jpayne@69: ** old one. ^Setting parameter X to NULL disables the progress handler. jpayne@69: ** ^The progress handler is also disabled by setting N to a value less jpayne@69: ** than 1. jpayne@69: ** jpayne@69: ** ^If the progress callback returns non-zero, the operation is jpayne@69: ** interrupted. This feature can be used to implement a jpayne@69: ** "Cancel" button on a GUI progress dialog box. jpayne@69: ** jpayne@69: ** The progress handler callback must not do anything that will modify jpayne@69: ** the database connection that invoked the progress handler. jpayne@69: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their jpayne@69: ** database connections for the meaning of "modify" in this paragraph. jpayne@69: ** jpayne@69: ** The progress handler callback would originally only be invoked from the jpayne@69: ** bytecode engine. It still might be invoked during [sqlite3_prepare()] jpayne@69: ** and similar because those routines might force a reparse of the schema jpayne@69: ** which involves running the bytecode engine. However, beginning with jpayne@69: ** SQLite version 3.41.0, the progress handler callback might also be jpayne@69: ** invoked directly from [sqlite3_prepare()] while analyzing and generating jpayne@69: ** code for complex queries. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Opening A New Database Connection jpayne@69: ** CONSTRUCTOR: sqlite3 jpayne@69: ** jpayne@69: ** ^These routines open an SQLite database file as specified by the jpayne@69: ** filename argument. ^The filename argument is interpreted as UTF-8 for jpayne@69: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte jpayne@69: ** order for sqlite3_open16(). ^(A [database connection] handle is usually jpayne@69: ** returned in *ppDb, even if an error occurs. The only exception is that jpayne@69: ** if SQLite is unable to allocate memory to hold the [sqlite3] object, jpayne@69: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] jpayne@69: ** object.)^ ^(If the database is opened (and/or created) successfully, then jpayne@69: ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The jpayne@69: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain jpayne@69: ** an English language description of the error following a failure of any jpayne@69: ** of the sqlite3_open() routines. jpayne@69: ** jpayne@69: ** ^The default encoding will be UTF-8 for databases created using jpayne@69: ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases jpayne@69: ** created using sqlite3_open16() will be UTF-16 in the native byte order. jpayne@69: ** jpayne@69: ** Whether or not an error occurs when it is opened, resources jpayne@69: ** associated with the [database connection] handle should be released by jpayne@69: ** passing it to [sqlite3_close()] when it is no longer required. jpayne@69: ** jpayne@69: ** The sqlite3_open_v2() interface works like sqlite3_open() jpayne@69: ** except that it accepts two additional parameters for additional control jpayne@69: ** over the new database connection. ^(The flags parameter to jpayne@69: ** sqlite3_open_v2() must include, at a minimum, one of the following jpayne@69: ** three flag combinations:)^ jpayne@69: ** jpayne@69: **
jpayne@69: ** ^(
[SQLITE_OPEN_READONLY]
jpayne@69: **
The database is opened in read-only mode. If the database does jpayne@69: ** not already exist, an error is returned.
)^ jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_READWRITE]
jpayne@69: **
The database is opened for reading and writing if possible, or jpayne@69: ** reading only if the file is write protected by the operating jpayne@69: ** system. In either case the database must already exist, otherwise jpayne@69: ** an error is returned. For historical reasons, if opening in jpayne@69: ** read-write mode fails due to OS-level permissions, an attempt is jpayne@69: ** made to open it in read-only mode. [sqlite3_db_readonly()] can be jpayne@69: ** used to determine whether the database is actually jpayne@69: ** read-write.
)^ jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
jpayne@69: **
The database is opened for reading and writing, and is created if jpayne@69: ** it does not already exist. This is the behavior that is always used for jpayne@69: ** sqlite3_open() and sqlite3_open16().
)^ jpayne@69: **
jpayne@69: ** jpayne@69: ** In addition to the required flags, the following optional flags are jpayne@69: ** also supported: jpayne@69: ** jpayne@69: **
jpayne@69: ** ^(
[SQLITE_OPEN_URI]
jpayne@69: **
The filename can be interpreted as a URI if this flag is set.
)^ jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_MEMORY]
jpayne@69: **
The database will be opened as an in-memory database. The database jpayne@69: ** is named by the "filename" argument for the purposes of cache-sharing, jpayne@69: ** if shared cache mode is enabled, but the "filename" is otherwise ignored. jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_NOMUTEX]
jpayne@69: **
The new database connection will use the "multi-thread" jpayne@69: ** [threading mode].)^ This means that separate threads are allowed jpayne@69: ** to use SQLite at the same time, as long as each thread is using jpayne@69: ** a different [database connection]. jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_FULLMUTEX]
jpayne@69: **
The new database connection will use the "serialized" jpayne@69: ** [threading mode].)^ This means the multiple threads can safely jpayne@69: ** attempt to use the same database connection at the same time. jpayne@69: ** (Mutexes will block any actual concurrency, but in this mode jpayne@69: ** there is no harm in trying.) jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_SHAREDCACHE]
jpayne@69: **
The database is opened [shared cache] enabled, overriding jpayne@69: ** the default shared cache setting provided by jpayne@69: ** [sqlite3_enable_shared_cache()].)^ jpayne@69: ** The [use of shared cache mode is discouraged] and hence shared cache jpayne@69: ** capabilities may be omitted from many builds of SQLite. In such cases, jpayne@69: ** this option is a no-op. jpayne@69: ** jpayne@69: ** ^(
[SQLITE_OPEN_PRIVATECACHE]
jpayne@69: **
The database is opened [shared cache] disabled, overriding jpayne@69: ** the default shared cache setting provided by jpayne@69: ** [sqlite3_enable_shared_cache()].)^ jpayne@69: ** jpayne@69: ** [[OPEN_EXRESCODE]] ^(
[SQLITE_OPEN_EXRESCODE]
jpayne@69: **
The database connection comes up in "extended result code mode". jpayne@69: ** In other words, the database behaves has if jpayne@69: ** [sqlite3_extended_result_codes(db,1)] where called on the database jpayne@69: ** connection as soon as the connection is created. In addition to setting jpayne@69: ** the extended result code mode, this flag also causes [sqlite3_open_v2()] jpayne@69: ** to return an extended result code.
jpayne@69: ** jpayne@69: ** [[OPEN_NOFOLLOW]] ^(
[SQLITE_OPEN_NOFOLLOW]
jpayne@69: **
The database filename is not allowed to contain a symbolic link
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** If the 3rd parameter to sqlite3_open_v2() is not one of the jpayne@69: ** required combinations shown above optionally combined with other jpayne@69: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] jpayne@69: ** then the behavior is undefined. Historic versions of SQLite jpayne@69: ** have silently ignored surplus bits in the flags parameter to jpayne@69: ** sqlite3_open_v2(), however that behavior might not be carried through jpayne@69: ** into future versions of SQLite and so applications should not rely jpayne@69: ** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op jpayne@69: ** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause jpayne@69: ** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE jpayne@69: ** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not jpayne@69: ** by sqlite3_open_v2(). jpayne@69: ** jpayne@69: ** ^The fourth parameter to sqlite3_open_v2() is the name of the jpayne@69: ** [sqlite3_vfs] object that defines the operating system interface that jpayne@69: ** the new database connection should use. ^If the fourth parameter is jpayne@69: ** a NULL pointer then the default [sqlite3_vfs] object is used. jpayne@69: ** jpayne@69: ** ^If the filename is ":memory:", then a private, temporary in-memory database jpayne@69: ** is created for the connection. ^This in-memory database will vanish when jpayne@69: ** the database connection is closed. Future versions of SQLite might jpayne@69: ** make use of additional special filenames that begin with the ":" character. jpayne@69: ** It is recommended that when a database filename actually does begin with jpayne@69: ** a ":" character you should prefix the filename with a pathname such as jpayne@69: ** "./" to avoid ambiguity. jpayne@69: ** jpayne@69: ** ^If the filename is an empty string, then a private, temporary jpayne@69: ** on-disk database will be created. ^This private database will be jpayne@69: ** automatically deleted as soon as the database connection is closed. jpayne@69: ** jpayne@69: ** [[URI filenames in sqlite3_open()]]

URI Filenames

jpayne@69: ** jpayne@69: ** ^If [URI filename] interpretation is enabled, and the filename argument jpayne@69: ** begins with "file:", then the filename is interpreted as a URI. ^URI jpayne@69: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is jpayne@69: ** set in the third argument to sqlite3_open_v2(), or if it has jpayne@69: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the jpayne@69: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. jpayne@69: ** URI filename interpretation is turned off jpayne@69: ** by default, but future releases of SQLite might enable URI filename jpayne@69: ** interpretation by default. See "[URI filenames]" for additional jpayne@69: ** information. jpayne@69: ** jpayne@69: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an jpayne@69: ** authority, then it must be either an empty string or the string jpayne@69: ** "localhost". ^If the authority is not an empty string or "localhost", an jpayne@69: ** error is returned to the caller. ^The fragment component of a URI, if jpayne@69: ** present, is ignored. jpayne@69: ** jpayne@69: ** ^SQLite uses the path component of the URI as the name of the disk file jpayne@69: ** which contains the database. ^If the path begins with a '/' character, jpayne@69: ** then it is interpreted as an absolute path. ^If the path does not begin jpayne@69: ** with a '/' (meaning that the authority section is omitted from the URI) jpayne@69: ** then the path is interpreted as a relative path. jpayne@69: ** ^(On windows, the first component of an absolute path jpayne@69: ** is a drive specification (e.g. "C:").)^ jpayne@69: ** jpayne@69: ** [[core URI query parameters]] jpayne@69: ** The query component of a URI may contain parameters that are interpreted jpayne@69: ** either by SQLite itself, or by a [VFS | custom VFS implementation]. jpayne@69: ** SQLite and its built-in [VFSes] interpret the jpayne@69: ** following query parameters: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** ^Specifying an unknown parameter in the query component of a URI is not an jpayne@69: ** error. Future versions of SQLite might understand additional query jpayne@69: ** parameters. See "[query parameters with special meaning to SQLite]" for jpayne@69: ** additional information. jpayne@69: ** jpayne@69: ** [[URI filename examples]]

URI filename examples

jpayne@69: ** jpayne@69: ** jpayne@69: **
URI filenames Results jpayne@69: **
file:data.db jpayne@69: ** Open the file "data.db" in the current directory. jpayne@69: **
file:/home/fred/data.db
jpayne@69: ** file:///home/fred/data.db
jpayne@69: ** file://localhost/home/fred/data.db
jpayne@69: ** Open the database file "/home/fred/data.db". jpayne@69: **
file://darkstar/home/fred/data.db jpayne@69: ** An error. "darkstar" is not a recognized authority. jpayne@69: **
jpayne@69: ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db jpayne@69: ** Windows only: Open the file "data.db" on fred's desktop on drive jpayne@69: ** C:. Note that the %20 escaping in this example is not strictly jpayne@69: ** necessary - space characters can be used literally jpayne@69: ** in URI filenames. jpayne@69: **
file:data.db?mode=ro&cache=private jpayne@69: ** Open file "data.db" in the current directory for read-only access. jpayne@69: ** Regardless of whether or not shared-cache mode is enabled by jpayne@69: ** default, use a private cache. jpayne@69: **
file:/home/fred/data.db?vfs=unix-dotfile jpayne@69: ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" jpayne@69: ** that uses dot-files in place of posix advisory locking. jpayne@69: **
file:data.db?mode=readonly jpayne@69: ** An error. "readonly" is not a valid option for the "mode" parameter. jpayne@69: ** Use "ro" instead: "file:data.db?mode=ro". jpayne@69: **
jpayne@69: ** jpayne@69: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and jpayne@69: ** query components of a URI. A hexadecimal escape sequence consists of a jpayne@69: ** percent sign - "%" - followed by exactly two hexadecimal digits jpayne@69: ** specifying an octet value. ^Before the path or query components of a jpayne@69: ** URI filename are interpreted, they are encoded using UTF-8 and all jpayne@69: ** hexadecimal escape sequences replaced by a single byte containing the jpayne@69: ** corresponding octet. If this process generates an invalid UTF-8 encoding, jpayne@69: ** the results are undefined. jpayne@69: ** jpayne@69: ** Note to Windows users: The encoding used for the filename argument jpayne@69: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever jpayne@69: ** codepage is currently defined. Filenames containing international jpayne@69: ** characters must be converted to UTF-8 prior to passing them into jpayne@69: ** sqlite3_open() or sqlite3_open_v2(). jpayne@69: ** jpayne@69: ** Note to Windows Runtime users: The temporary directory must be set jpayne@69: ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various jpayne@69: ** features that require the use of temporary files may fail. jpayne@69: ** jpayne@69: ** See also: [sqlite3_temp_directory] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_open( jpayne@69: const char *filename, /* Database filename (UTF-8) */ jpayne@69: sqlite3 **ppDb /* OUT: SQLite db handle */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_open16( jpayne@69: const void *filename, /* Database filename (UTF-16) */ jpayne@69: sqlite3 **ppDb /* OUT: SQLite db handle */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_open_v2( jpayne@69: const char *filename, /* Database filename (UTF-8) */ jpayne@69: sqlite3 **ppDb, /* OUT: SQLite db handle */ jpayne@69: int flags, /* Flags */ jpayne@69: const char *zVfs /* Name of VFS module to use */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain Values For URI Parameters jpayne@69: ** jpayne@69: ** These are utility routines, useful to [VFS|custom VFS implementations], jpayne@69: ** that check if a database file was a URI that contained a specific query jpayne@69: ** parameter, and if so obtains the value of that query parameter. jpayne@69: ** jpayne@69: ** The first parameter to these interfaces (hereafter referred to jpayne@69: ** as F) must be one of: jpayne@69: ** jpayne@69: ** If the F parameter is not one of the above, then the behavior is jpayne@69: ** undefined and probably undesirable. Older versions of SQLite were jpayne@69: ** more tolerant of invalid F parameters than newer versions. jpayne@69: ** jpayne@69: ** If F is a suitable filename (as described in the previous paragraph) jpayne@69: ** and if P is the name of the query parameter, then jpayne@69: ** sqlite3_uri_parameter(F,P) returns the value of the P jpayne@69: ** parameter if it exists or a NULL pointer if P does not appear as a jpayne@69: ** query parameter on F. If P is a query parameter of F and it jpayne@69: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns jpayne@69: ** a pointer to an empty string. jpayne@69: ** jpayne@69: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean jpayne@69: ** parameter and returns true (1) or false (0) according to the value jpayne@69: ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the jpayne@69: ** value of query parameter P is one of "yes", "true", or "on" in any jpayne@69: ** case or if the value begins with a non-zero number. The jpayne@69: ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of jpayne@69: ** query parameter P is one of "no", "false", or "off" in any case or jpayne@69: ** if the value begins with a numeric zero. If P is not a query jpayne@69: ** parameter on F or if the value of P does not match any of the jpayne@69: ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). jpayne@69: ** jpayne@69: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a jpayne@69: ** 64-bit signed integer and returns that integer, or D if P does not jpayne@69: ** exist. If the value of P is something other than an integer, then jpayne@69: ** zero is returned. jpayne@69: ** jpayne@69: ** The sqlite3_uri_key(F,N) returns a pointer to the name (not jpayne@69: ** the value) of the N-th query parameter for filename F, or a NULL jpayne@69: ** pointer if N is less than zero or greater than the number of query jpayne@69: ** parameters minus 1. The N value is zero-based so N should be 0 to obtain jpayne@69: ** the name of the first query parameter, 1 for the second parameter, and jpayne@69: ** so forth. jpayne@69: ** jpayne@69: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and jpayne@69: ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and jpayne@69: ** is not a database file pathname pointer that the SQLite core passed jpayne@69: ** into the xOpen VFS method, then the behavior of this routine is undefined jpayne@69: ** and probably undesirable. jpayne@69: ** jpayne@69: ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F jpayne@69: ** parameter can also be the name of a rollback journal file or WAL file jpayne@69: ** in addition to the main database file. Prior to version 3.31.0, these jpayne@69: ** routines would only work if F was the name of the main database file. jpayne@69: ** When the F parameter is the name of the rollback journal or WAL file, jpayne@69: ** it has access to all the same query parameters as were found on the jpayne@69: ** main database file. jpayne@69: ** jpayne@69: ** See the [URI filename] documentation for additional information. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam); jpayne@69: SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64); jpayne@69: SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Translate filenames jpayne@69: ** jpayne@69: ** These routines are available to [VFS|custom VFS implementations] for jpayne@69: ** translating filenames between the main database file, the journal file, jpayne@69: ** and the WAL file. jpayne@69: ** jpayne@69: ** If F is the name of an sqlite database file, journal file, or WAL file jpayne@69: ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) jpayne@69: ** returns the name of the corresponding database file. jpayne@69: ** jpayne@69: ** If F is the name of an sqlite database file, journal file, or WAL file jpayne@69: ** passed by the SQLite core into the VFS, or if F is a database filename jpayne@69: ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) jpayne@69: ** returns the name of the corresponding rollback journal file. jpayne@69: ** jpayne@69: ** If F is the name of an sqlite database file, journal file, or WAL file jpayne@69: ** that was passed by the SQLite core into the VFS, or if F is a database jpayne@69: ** filename obtained from [sqlite3_db_filename()], then jpayne@69: ** sqlite3_filename_wal(F) returns the name of the corresponding jpayne@69: ** WAL file. jpayne@69: ** jpayne@69: ** In all of the above, if F is not the name of a database, journal or WAL jpayne@69: ** filename passed into the VFS from the SQLite core and F is not the jpayne@69: ** return value from [sqlite3_db_filename()], then the result is jpayne@69: ** undefined and is likely a memory access violation. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_filename_database(sqlite3_filename); jpayne@69: SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename); jpayne@69: SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database File Corresponding To A Journal jpayne@69: ** jpayne@69: ** ^If X is the name of a rollback or WAL-mode journal file that is jpayne@69: ** passed into the xOpen method of [sqlite3_vfs], then jpayne@69: ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] jpayne@69: ** object that represents the main database file. jpayne@69: ** jpayne@69: ** This routine is intended for use in custom [VFS] implementations jpayne@69: ** only. It is not a general-purpose interface. jpayne@69: ** The argument sqlite3_file_object(X) must be a filename pointer that jpayne@69: ** has been passed into [sqlite3_vfs].xOpen method where the jpayne@69: ** flags parameter to xOpen contains one of the bits jpayne@69: ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use jpayne@69: ** of this routine results in undefined and probably undesirable jpayne@69: ** behavior. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create and Destroy VFS Filenames jpayne@69: ** jpayne@69: ** These interfaces are provided for use by [VFS shim] implementations and jpayne@69: ** are not useful outside of that context. jpayne@69: ** jpayne@69: ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of jpayne@69: ** database filename D with corresponding journal file J and WAL file W and jpayne@69: ** with N URI parameters key/values pairs in the array P. The result from jpayne@69: ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that jpayne@69: ** is safe to pass to routines like: jpayne@69: ** jpayne@69: ** If a memory allocation error occurs, sqlite3_create_filename() might jpayne@69: ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) jpayne@69: ** must be released by a corresponding call to sqlite3_free_filename(Y). jpayne@69: ** jpayne@69: ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array jpayne@69: ** of 2*N pointers to strings. Each pair of pointers in this array corresponds jpayne@69: ** to a key and value for a query parameter. The P parameter may be a NULL jpayne@69: ** pointer if N is zero. None of the 2*N pointers in the P array may be jpayne@69: ** NULL pointers and key pointers should not be empty strings. jpayne@69: ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may jpayne@69: ** be NULL pointers, though they can be empty strings. jpayne@69: ** jpayne@69: ** The sqlite3_free_filename(Y) routine releases a memory allocation jpayne@69: ** previously obtained from sqlite3_create_filename(). Invoking jpayne@69: ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. jpayne@69: ** jpayne@69: ** If the Y parameter to sqlite3_free_filename(Y) is anything other jpayne@69: ** than a NULL pointer or a pointer previously acquired from jpayne@69: ** sqlite3_create_filename(), then bad things such as heap jpayne@69: ** corruption or segfaults may occur. The value Y should not be jpayne@69: ** used again after sqlite3_free_filename(Y) has been called. This means jpayne@69: ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, jpayne@69: ** then the corresponding [sqlite3_module.xClose() method should also be jpayne@69: ** invoked prior to calling sqlite3_free_filename(Y). jpayne@69: */ jpayne@69: SQLITE_API sqlite3_filename sqlite3_create_filename( jpayne@69: const char *zDatabase, jpayne@69: const char *zJournal, jpayne@69: const char *zWal, jpayne@69: int nParam, jpayne@69: const char **azParam jpayne@69: ); jpayne@69: SQLITE_API void sqlite3_free_filename(sqlite3_filename); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Error Codes And Messages jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^If the most recent sqlite3_* API call associated with jpayne@69: ** [database connection] D failed, then the sqlite3_errcode(D) interface jpayne@69: ** returns the numeric [result code] or [extended result code] for that jpayne@69: ** API call. jpayne@69: ** ^The sqlite3_extended_errcode() jpayne@69: ** interface is the same except that it always returns the jpayne@69: ** [extended result code] even when extended result codes are jpayne@69: ** disabled. jpayne@69: ** jpayne@69: ** The values returned by sqlite3_errcode() and/or jpayne@69: ** sqlite3_extended_errcode() might change with each API call. jpayne@69: ** Except, there are some interfaces that are guaranteed to never jpayne@69: ** change the value of the error code. The error-code preserving jpayne@69: ** interfaces include the following: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language jpayne@69: ** text that describes the error, as either UTF-8 or UTF-16 respectively, jpayne@69: ** or NULL if no error message is available. jpayne@69: ** (See how SQLite handles [invalid UTF] for exceptions to this rule.) jpayne@69: ** ^(Memory to hold the error message string is managed internally. jpayne@69: ** The application does not need to worry about freeing the result. jpayne@69: ** However, the error string might be overwritten or deallocated by jpayne@69: ** subsequent calls to other SQLite interface functions.)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_errstr(E) interface returns the English-language text jpayne@69: ** that describes the [result code] E, as UTF-8, or NULL if E is not an jpayne@69: ** result code for which a text error message is available. jpayne@69: ** ^(Memory to hold the error message string is managed internally jpayne@69: ** and must not be freed by the application)^. jpayne@69: ** jpayne@69: ** ^If the most recent error references a specific token in the input jpayne@69: ** SQL, the sqlite3_error_offset() interface returns the byte offset jpayne@69: ** of the start of that token. ^The byte offset returned by jpayne@69: ** sqlite3_error_offset() assumes that the input SQL is UTF8. jpayne@69: ** ^If the most recent error does not reference a specific token in the input jpayne@69: ** SQL, then the sqlite3_error_offset() function returns -1. jpayne@69: ** jpayne@69: ** When the serialized [threading mode] is in use, it might be the jpayne@69: ** case that a second error occurs on a separate thread in between jpayne@69: ** the time of the first error and the call to these interfaces. jpayne@69: ** When that happens, the second error will be reported since these jpayne@69: ** interfaces always report the most recent result. To avoid jpayne@69: ** this, each thread can obtain exclusive use of the [database connection] D jpayne@69: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning jpayne@69: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after jpayne@69: ** all calls to the interfaces listed here are completed. jpayne@69: ** jpayne@69: ** If an interface fails with SQLITE_MISUSE, that means the interface jpayne@69: ** was invoked incorrectly by the application. In that case, the jpayne@69: ** error code and message may or may not be set. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_errcode(sqlite3 *db); jpayne@69: SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); jpayne@69: SQLITE_API const char *sqlite3_errmsg(sqlite3*); jpayne@69: SQLITE_API const void *sqlite3_errmsg16(sqlite3*); jpayne@69: SQLITE_API const char *sqlite3_errstr(int); jpayne@69: SQLITE_API int sqlite3_error_offset(sqlite3 *db); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepared Statement Object jpayne@69: ** KEYWORDS: {prepared statement} {prepared statements} jpayne@69: ** jpayne@69: ** An instance of this object represents a single SQL statement that jpayne@69: ** has been compiled into binary form and is ready to be evaluated. jpayne@69: ** jpayne@69: ** Think of each SQL statement as a separate computer program. The jpayne@69: ** original SQL text is source code. A prepared statement object jpayne@69: ** is the compiled object code. All SQL must be converted into a jpayne@69: ** prepared statement before it can be run. jpayne@69: ** jpayne@69: ** The life-cycle of a prepared statement object usually goes like this: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  1. Create the prepared statement object using [sqlite3_prepare_v2()]. jpayne@69: **
  2. Bind values to [parameters] using the sqlite3_bind_*() jpayne@69: ** interfaces. jpayne@69: **
  3. Run the SQL by calling [sqlite3_step()] one or more times. jpayne@69: **
  4. Reset the prepared statement using [sqlite3_reset()] then go back jpayne@69: ** to step 2. Do this zero or more times. jpayne@69: **
  5. Destroy the object using [sqlite3_finalize()]. jpayne@69: **
jpayne@69: */ jpayne@69: typedef struct sqlite3_stmt sqlite3_stmt; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Run-time Limits jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^(This interface allows the size of various constructs to be limited jpayne@69: ** on a connection by connection basis. The first parameter is the jpayne@69: ** [database connection] whose limit is to be set or queried. The jpayne@69: ** second parameter is one of the [limit categories] that define a jpayne@69: ** class of constructs to be size limited. The third parameter is the jpayne@69: ** new limit for that construct.)^ jpayne@69: ** jpayne@69: ** ^If the new limit is a negative number, the limit is unchanged. jpayne@69: ** ^(For each limit category SQLITE_LIMIT_NAME there is a jpayne@69: ** [limits | hard upper bound] jpayne@69: ** set at compile-time by a C preprocessor macro called jpayne@69: ** [limits | SQLITE_MAX_NAME]. jpayne@69: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ jpayne@69: ** ^Attempts to increase a limit above its hard upper bound are jpayne@69: ** silently truncated to the hard upper bound. jpayne@69: ** jpayne@69: ** ^Regardless of whether or not the limit was changed, the jpayne@69: ** [sqlite3_limit()] interface returns the prior value of the limit. jpayne@69: ** ^Hence, to find the current value of a limit without changing it, jpayne@69: ** simply invoke this interface with the third parameter set to -1. jpayne@69: ** jpayne@69: ** Run-time limits are intended for use in applications that manage jpayne@69: ** both their own internal database and also databases that are controlled jpayne@69: ** by untrusted external sources. An example application might be a jpayne@69: ** web browser that has its own databases for storing history and jpayne@69: ** separate databases controlled by JavaScript applications downloaded jpayne@69: ** off the Internet. The internal databases can be given the jpayne@69: ** large, default limits. Databases managed by external sources can jpayne@69: ** be given much smaller limits designed to prevent a denial of service jpayne@69: ** attack. Developers might also want to use the [sqlite3_set_authorizer()] jpayne@69: ** interface to further control untrusted SQL. The size of the database jpayne@69: ** created by an untrusted script can be contained using the jpayne@69: ** [max_page_count] [PRAGMA]. jpayne@69: ** jpayne@69: ** New run-time limit categories may be added in future releases. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Run-Time Limit Categories jpayne@69: ** KEYWORDS: {limit category} {*limit categories} jpayne@69: ** jpayne@69: ** These constants define various performance limits jpayne@69: ** that can be lowered at run-time using [sqlite3_limit()]. jpayne@69: ** The synopsis of the meanings of the various limits is shown below. jpayne@69: ** Additional information is available at [limits | Limits in SQLite]. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_LIMIT_LENGTH]] ^(
SQLITE_LIMIT_LENGTH
jpayne@69: **
The maximum size of any string or BLOB or table row, in bytes.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(
SQLITE_LIMIT_SQL_LENGTH
jpayne@69: **
The maximum length of an SQL statement, in bytes.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_COLUMN]] ^(
SQLITE_LIMIT_COLUMN
jpayne@69: **
The maximum number of columns in a table definition or in the jpayne@69: ** result set of a [SELECT] or the maximum number of columns in an index jpayne@69: ** or in an ORDER BY or GROUP BY clause.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(
SQLITE_LIMIT_EXPR_DEPTH
jpayne@69: **
The maximum depth of the parse tree on any expression.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(
SQLITE_LIMIT_COMPOUND_SELECT
jpayne@69: **
The maximum number of terms in a compound SELECT statement.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_VDBE_OP]] ^(
SQLITE_LIMIT_VDBE_OP
jpayne@69: **
The maximum number of instructions in a virtual machine program jpayne@69: ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or jpayne@69: ** the equivalent tries to allocate space for more than this many opcodes jpayne@69: ** in a single prepared statement, an SQLITE_NOMEM error is returned.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(
SQLITE_LIMIT_FUNCTION_ARG
jpayne@69: **
The maximum number of arguments on a function.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_ATTACHED]] ^(
SQLITE_LIMIT_ATTACHED
jpayne@69: **
The maximum number of [ATTACH | attached databases].)^
jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] jpayne@69: ** ^(
SQLITE_LIMIT_LIKE_PATTERN_LENGTH
jpayne@69: **
The maximum length of the pattern argument to the [LIKE] or jpayne@69: ** [GLOB] operators.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] jpayne@69: ** ^(
SQLITE_LIMIT_VARIABLE_NUMBER
jpayne@69: **
The maximum index number of any [parameter] in an SQL statement.)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(
SQLITE_LIMIT_TRIGGER_DEPTH
jpayne@69: **
The maximum depth of recursion for triggers.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(
SQLITE_LIMIT_WORKER_THREADS
jpayne@69: **
The maximum number of auxiliary worker threads that a single jpayne@69: ** [prepared statement] may start.
)^ jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_LIMIT_LENGTH 0 jpayne@69: #define SQLITE_LIMIT_SQL_LENGTH 1 jpayne@69: #define SQLITE_LIMIT_COLUMN 2 jpayne@69: #define SQLITE_LIMIT_EXPR_DEPTH 3 jpayne@69: #define SQLITE_LIMIT_COMPOUND_SELECT 4 jpayne@69: #define SQLITE_LIMIT_VDBE_OP 5 jpayne@69: #define SQLITE_LIMIT_FUNCTION_ARG 6 jpayne@69: #define SQLITE_LIMIT_ATTACHED 7 jpayne@69: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 jpayne@69: #define SQLITE_LIMIT_VARIABLE_NUMBER 9 jpayne@69: #define SQLITE_LIMIT_TRIGGER_DEPTH 10 jpayne@69: #define SQLITE_LIMIT_WORKER_THREADS 11 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepare Flags jpayne@69: ** jpayne@69: ** These constants define various flags that can be passed into jpayne@69: ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and jpayne@69: ** [sqlite3_prepare16_v3()] interfaces. jpayne@69: ** jpayne@69: ** New flags may be added in future releases of SQLite. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_PREPARE_PERSISTENT]] ^(
SQLITE_PREPARE_PERSISTENT
jpayne@69: **
The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner jpayne@69: ** that the prepared statement will be retained for a long time and jpayne@69: ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] jpayne@69: ** and [sqlite3_prepare16_v3()] assume that the prepared statement will jpayne@69: ** be used just once or at most a few times and then destroyed using jpayne@69: ** [sqlite3_finalize()] relatively soon. The current implementation acts jpayne@69: ** on this hint by avoiding the use of [lookaside memory] so as not to jpayne@69: ** deplete the limited store of lookaside memory. Future versions of jpayne@69: ** SQLite may act on this hint differently. jpayne@69: ** jpayne@69: ** [[SQLITE_PREPARE_NORMALIZE]]
SQLITE_PREPARE_NORMALIZE
jpayne@69: **
The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used jpayne@69: ** to be required for any prepared statement that wanted to use the jpayne@69: ** [sqlite3_normalized_sql()] interface. However, the jpayne@69: ** [sqlite3_normalized_sql()] interface is now available to all jpayne@69: ** prepared statements, regardless of whether or not they use this jpayne@69: ** flag. jpayne@69: ** jpayne@69: ** [[SQLITE_PREPARE_NO_VTAB]]
SQLITE_PREPARE_NO_VTAB
jpayne@69: **
The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler jpayne@69: ** to return an error (error code SQLITE_ERROR) if the statement uses jpayne@69: ** any virtual tables. jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_PREPARE_PERSISTENT 0x01 jpayne@69: #define SQLITE_PREPARE_NORMALIZE 0x02 jpayne@69: #define SQLITE_PREPARE_NO_VTAB 0x04 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Compiling An SQL Statement jpayne@69: ** KEYWORDS: {SQL statement compiler} jpayne@69: ** METHOD: sqlite3 jpayne@69: ** CONSTRUCTOR: sqlite3_stmt jpayne@69: ** jpayne@69: ** To execute an SQL statement, it must first be compiled into a byte-code jpayne@69: ** program using one of these routines. Or, in other words, these routines jpayne@69: ** are constructors for the [prepared statement] object. jpayne@69: ** jpayne@69: ** The preferred routine to use is [sqlite3_prepare_v2()]. The jpayne@69: ** [sqlite3_prepare()] interface is legacy and should be avoided. jpayne@69: ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used jpayne@69: ** for special purposes. jpayne@69: ** jpayne@69: ** The use of the UTF-8 interfaces is preferred, as SQLite currently jpayne@69: ** does all parsing using UTF-8. The UTF-16 interfaces are provided jpayne@69: ** as a convenience. The UTF-16 interfaces work by converting the jpayne@69: ** input text into UTF-8, then invoking the corresponding UTF-8 interface. jpayne@69: ** jpayne@69: ** The first argument, "db", is a [database connection] obtained from a jpayne@69: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or jpayne@69: ** [sqlite3_open16()]. The database connection must not have been closed. jpayne@69: ** jpayne@69: ** The second argument, "zSql", is the statement to be compiled, encoded jpayne@69: ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), jpayne@69: ** and sqlite3_prepare_v3() jpayne@69: ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), jpayne@69: ** and sqlite3_prepare16_v3() use UTF-16. jpayne@69: ** jpayne@69: ** ^If the nByte argument is negative, then zSql is read up to the jpayne@69: ** first zero terminator. ^If nByte is positive, then it is the jpayne@69: ** number of bytes read from zSql. ^If nByte is zero, then no prepared jpayne@69: ** statement is generated. jpayne@69: ** If the caller knows that the supplied string is nul-terminated, then jpayne@69: ** there is a small performance advantage to passing an nByte parameter that jpayne@69: ** is the number of bytes in the input string including jpayne@69: ** the nul-terminator. jpayne@69: ** jpayne@69: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte jpayne@69: ** past the end of the first SQL statement in zSql. These routines only jpayne@69: ** compile the first statement in zSql, so *pzTail is left pointing to jpayne@69: ** what remains uncompiled. jpayne@69: ** jpayne@69: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be jpayne@69: ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set jpayne@69: ** to NULL. ^If the input text contains no SQL (if the input is an empty jpayne@69: ** string or a comment) then *ppStmt is set to NULL. jpayne@69: ** The calling procedure is responsible for deleting the compiled jpayne@69: ** SQL statement using [sqlite3_finalize()] after it has finished with it. jpayne@69: ** ppStmt may not be NULL. jpayne@69: ** jpayne@69: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; jpayne@69: ** otherwise an [error code] is returned. jpayne@69: ** jpayne@69: ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), jpayne@69: ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. jpayne@69: ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) jpayne@69: ** are retained for backwards compatibility, but their use is discouraged. jpayne@69: ** ^In the "vX" interfaces, the prepared statement jpayne@69: ** that is returned (the [sqlite3_stmt] object) contains a copy of the jpayne@69: ** original SQL text. This causes the [sqlite3_step()] interface to jpayne@69: ** behave differently in three ways: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  1. jpayne@69: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it jpayne@69: ** always used to do, [sqlite3_step()] will automatically recompile the SQL jpayne@69: ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] jpayne@69: ** retries will occur before sqlite3_step() gives up and returns an error. jpayne@69: **
    2. jpayne@69: ** jpayne@69: **
  2. jpayne@69: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed jpayne@69: ** [error codes] or [extended error codes]. ^The legacy behavior was that jpayne@69: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code jpayne@69: ** and the application would have to make a second call to [sqlite3_reset()] jpayne@69: ** in order to find the underlying cause of the problem. With the "v2" prepare jpayne@69: ** interfaces, the underlying reason for the error is returned immediately. jpayne@69: **
    3. jpayne@69: ** jpayne@69: **
  3. jpayne@69: ** ^If the specific value bound to a [parameter | host parameter] in the jpayne@69: ** WHERE clause might influence the choice of query plan for a statement, jpayne@69: ** then the statement will be automatically recompiled, as if there had been jpayne@69: ** a schema change, on the first [sqlite3_step()] call following any change jpayne@69: ** to the [sqlite3_bind_text | bindings] of that [parameter]. jpayne@69: ** ^The specific value of a WHERE-clause [parameter] might influence the jpayne@69: ** choice of query plan if the parameter is the left-hand side of a [LIKE] jpayne@69: ** or [GLOB] operator or if the parameter is compared to an indexed column jpayne@69: ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. jpayne@69: **
    4. jpayne@69: **
jpayne@69: ** jpayne@69: **

^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having jpayne@69: ** the extra prepFlags parameter, which is a bit array consisting of zero or jpayne@69: ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The jpayne@69: ** sqlite3_prepare_v2() interface works exactly the same as jpayne@69: ** sqlite3_prepare_v3() with a zero prepFlags parameter. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_prepare( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const char *zSql, /* SQL statement, UTF-8 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const char **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_prepare_v2( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const char *zSql, /* SQL statement, UTF-8 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const char **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_prepare_v3( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const char *zSql, /* SQL statement, UTF-8 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const char **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_prepare16( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const void *zSql, /* SQL statement, UTF-16 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const void **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_prepare16_v2( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const void *zSql, /* SQL statement, UTF-16 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const void **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_prepare16_v3( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const void *zSql, /* SQL statement, UTF-16 encoded */ jpayne@69: int nByte, /* Maximum length of zSql in bytes. */ jpayne@69: unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ jpayne@69: sqlite3_stmt **ppStmt, /* OUT: Statement handle */ jpayne@69: const void **pzTail /* OUT: Pointer to unused portion of zSql */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Retrieving Statement SQL jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 jpayne@69: ** SQL text used to create [prepared statement] P if P was jpayne@69: ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], jpayne@69: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. jpayne@69: ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 jpayne@69: ** string containing the SQL text of prepared statement P with jpayne@69: ** [bound parameters] expanded. jpayne@69: ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 jpayne@69: ** string containing the normalized SQL text of prepared statement P. The jpayne@69: ** semantics used to normalize a SQL statement are unspecified and subject jpayne@69: ** to change. At a minimum, literal values will be replaced with suitable jpayne@69: ** placeholders. jpayne@69: ** jpayne@69: ** ^(For example, if a prepared statement is created using the SQL jpayne@69: ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 jpayne@69: ** and parameter :xyz is unbound, then sqlite3_sql() will return jpayne@69: ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() jpayne@69: ** will return "SELECT 2345,NULL".)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory jpayne@69: ** is available to hold the result, or if the result would exceed the jpayne@69: ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. jpayne@69: ** jpayne@69: ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of jpayne@69: ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time jpayne@69: ** option causes sqlite3_expanded_sql() to always return NULL. jpayne@69: ** jpayne@69: ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) jpayne@69: ** are managed by SQLite and are automatically freed when the prepared jpayne@69: ** statement is finalized. jpayne@69: ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, jpayne@69: ** is obtained from [sqlite3_malloc()] and must be freed by the application jpayne@69: ** by passing it to [sqlite3_free()]. jpayne@69: ** jpayne@69: ** ^The sqlite3_normalized_sql() interface is only available if jpayne@69: ** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); jpayne@69: SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); jpayne@69: #ifdef SQLITE_ENABLE_NORMALIZE jpayne@69: SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine If An SQL Statement Writes The Database jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if jpayne@69: ** and only if the [prepared statement] X makes no direct changes to jpayne@69: ** the content of the database file. jpayne@69: ** jpayne@69: ** Note that [application-defined SQL functions] or jpayne@69: ** [virtual tables] might change the database indirectly as a side effect. jpayne@69: ** ^(For example, if an application defines a function "eval()" that jpayne@69: ** calls [sqlite3_exec()], then the following SQL statement would jpayne@69: ** change the database file through side-effects: jpayne@69: ** jpayne@69: ** 

jpayne@69: **    SELECT eval('DELETE FROM t1') FROM t2;
jpayne@69: **
jpayne@69: ** jpayne@69: ** But because the [SELECT] statement does not change the database file jpayne@69: ** directly, sqlite3_stmt_readonly() would still return true.)^ jpayne@69: ** jpayne@69: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], jpayne@69: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, jpayne@69: ** since the statements themselves do not actually modify the database but jpayne@69: ** rather they control the timing of when other statements modify the jpayne@69: ** database. ^The [ATTACH] and [DETACH] statements also cause jpayne@69: ** sqlite3_stmt_readonly() to return true since, while those statements jpayne@69: ** change the configuration of a database connection, they do not make jpayne@69: ** changes to the content of the database files on disk. jpayne@69: ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since jpayne@69: ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and jpayne@69: ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so jpayne@69: ** sqlite3_stmt_readonly() returns false for those commands. jpayne@69: ** jpayne@69: ** ^This routine returns false if there is any possibility that the jpayne@69: ** statement might change the database file. ^A false return does jpayne@69: ** not guarantee that the statement will change the database file. jpayne@69: ** ^For example, an UPDATE statement might have a WHERE clause that jpayne@69: ** makes it a no-op, but the sqlite3_stmt_readonly() result would still jpayne@69: ** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a jpayne@69: ** read-only no-op if the table already exists, but jpayne@69: ** sqlite3_stmt_readonly() still returns false for such a statement. jpayne@69: ** jpayne@69: ** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] jpayne@69: ** statement, then sqlite3_stmt_readonly(X) returns the same value as jpayne@69: ** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the jpayne@69: ** prepared statement S is an EXPLAIN statement, or 2 if the jpayne@69: ** statement S is an EXPLAIN QUERY PLAN. jpayne@69: ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is jpayne@69: ** an ordinary statement or a NULL pointer. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN jpayne@69: ** setting for [prepared statement] S. If E is zero, then S becomes jpayne@69: ** a normal prepared statement. If E is 1, then S behaves as if jpayne@69: ** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if jpayne@69: ** its SQL text began with "[EXPLAIN QUERY PLAN]". jpayne@69: ** jpayne@69: ** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared. jpayne@69: ** SQLite tries to avoid a reprepare, but a reprepare might be necessary jpayne@69: ** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode. jpayne@69: ** jpayne@69: ** Because of the potential need to reprepare, a call to jpayne@69: ** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be jpayne@69: ** reprepared because it was created using [sqlite3_prepare()] instead of jpayne@69: ** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and jpayne@69: ** hence has no saved SQL text with which to reprepare. jpayne@69: ** jpayne@69: ** Changing the explain setting for a prepared statement does not change jpayne@69: ** the original SQL text for the statement. Hence, if the SQL text originally jpayne@69: ** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0) jpayne@69: ** is called to convert the statement into an ordinary statement, the EXPLAIN jpayne@69: ** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S) jpayne@69: ** output, even though the statement now acts like a normal SQL statement. jpayne@69: ** jpayne@69: ** This routine returns SQLITE_OK if the explain mode is successfully jpayne@69: ** changed, or an error code if the explain mode could not be changed. jpayne@69: ** The explain mode cannot be changed while a statement is active. jpayne@69: ** Hence, it is good practice to call [sqlite3_reset(S)] jpayne@69: ** immediately prior to calling sqlite3_stmt_explain(S,E). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the jpayne@69: ** [prepared statement] S has been stepped at least once using jpayne@69: ** [sqlite3_step(S)] but has neither run to completion (returned jpayne@69: ** [SQLITE_DONE] from [sqlite3_step(S)]) nor jpayne@69: ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) jpayne@69: ** interface returns false if S is a NULL pointer. If S is not a jpayne@69: ** NULL pointer and is not a pointer to a valid [prepared statement] jpayne@69: ** object, then the behavior is undefined and probably undesirable. jpayne@69: ** jpayne@69: ** This interface can be used in combination [sqlite3_next_stmt()] jpayne@69: ** to locate all prepared statements associated with a database jpayne@69: ** connection that are in need of being reset. This can be used, jpayne@69: ** for example, in diagnostic routines to search for prepared jpayne@69: ** statements that are holding a transaction open. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Dynamically Typed Value Object jpayne@69: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} jpayne@69: ** jpayne@69: ** SQLite uses the sqlite3_value object to represent all values jpayne@69: ** that can be stored in a database table. SQLite uses dynamic typing jpayne@69: ** for the values it stores. ^Values stored in sqlite3_value objects jpayne@69: ** can be integers, floating point values, strings, BLOBs, or NULL. jpayne@69: ** jpayne@69: ** An sqlite3_value object may be either "protected" or "unprotected". jpayne@69: ** Some interfaces require a protected sqlite3_value. Other interfaces jpayne@69: ** will accept either a protected or an unprotected sqlite3_value. jpayne@69: ** Every interface that accepts sqlite3_value arguments specifies jpayne@69: ** whether or not it requires a protected sqlite3_value. The jpayne@69: ** [sqlite3_value_dup()] interface can be used to construct a new jpayne@69: ** protected sqlite3_value from an unprotected sqlite3_value. jpayne@69: ** jpayne@69: ** The terms "protected" and "unprotected" refer to whether or not jpayne@69: ** a mutex is held. An internal mutex is held for a protected jpayne@69: ** sqlite3_value object but no mutex is held for an unprotected jpayne@69: ** sqlite3_value object. If SQLite is compiled to be single-threaded jpayne@69: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) jpayne@69: ** or if SQLite is run in one of reduced mutex modes jpayne@69: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] jpayne@69: ** then there is no distinction between protected and unprotected jpayne@69: ** sqlite3_value objects and they can be used interchangeably. However, jpayne@69: ** for maximum code portability it is recommended that applications jpayne@69: ** still make the distinction between protected and unprotected jpayne@69: ** sqlite3_value objects even when not strictly required. jpayne@69: ** jpayne@69: ** ^The sqlite3_value objects that are passed as parameters into the jpayne@69: ** implementation of [application-defined SQL functions] are protected. jpayne@69: ** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] jpayne@69: ** are protected. jpayne@69: ** ^The sqlite3_value object returned by jpayne@69: ** [sqlite3_column_value()] is unprotected. jpayne@69: ** Unprotected sqlite3_value objects may only be used as arguments jpayne@69: ** to [sqlite3_result_value()], [sqlite3_bind_value()], and jpayne@69: ** [sqlite3_value_dup()]. jpayne@69: ** The [sqlite3_value_blob | sqlite3_value_type()] family of jpayne@69: ** interfaces require protected sqlite3_value objects. jpayne@69: */ jpayne@69: typedef struct sqlite3_value sqlite3_value; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: SQL Function Context Object jpayne@69: ** jpayne@69: ** The context in which an SQL function executes is stored in an jpayne@69: ** sqlite3_context object. ^A pointer to an sqlite3_context object jpayne@69: ** is always first parameter to [application-defined SQL functions]. jpayne@69: ** The application-defined SQL function implementation will pass this jpayne@69: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], jpayne@69: ** [sqlite3_aggregate_context()], [sqlite3_user_data()], jpayne@69: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], jpayne@69: ** and/or [sqlite3_set_auxdata()]. jpayne@69: */ jpayne@69: typedef struct sqlite3_context sqlite3_context; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Binding Values To Prepared Statements jpayne@69: ** KEYWORDS: {host parameter} {host parameters} {host parameter name} jpayne@69: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, jpayne@69: ** literals may be replaced by a [parameter] that matches one of following jpayne@69: ** templates: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** In the templates above, NNN represents an integer literal, jpayne@69: ** and VVV represents an alphanumeric identifier.)^ ^The values of these jpayne@69: ** parameters (also called "host parameter names" or "SQL parameters") jpayne@69: ** can be set using the sqlite3_bind_*() routines defined here. jpayne@69: ** jpayne@69: ** ^The first argument to the sqlite3_bind_*() routines is always jpayne@69: ** a pointer to the [sqlite3_stmt] object returned from jpayne@69: ** [sqlite3_prepare_v2()] or its variants. jpayne@69: ** jpayne@69: ** ^The second argument is the index of the SQL parameter to be set. jpayne@69: ** ^The leftmost SQL parameter has an index of 1. ^When the same named jpayne@69: ** SQL parameter is used more than once, second and subsequent jpayne@69: ** occurrences have the same index as the first occurrence. jpayne@69: ** ^The index for named parameters can be looked up using the jpayne@69: ** [sqlite3_bind_parameter_index()] API if desired. ^The index jpayne@69: ** for "?NNN" parameters is the value of NNN. jpayne@69: ** ^The NNN value must be between 1 and the [sqlite3_limit()] jpayne@69: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). jpayne@69: ** jpayne@69: ** ^The third argument is the value to bind to the parameter. jpayne@69: ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() jpayne@69: ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter jpayne@69: ** is ignored and the end result is the same as sqlite3_bind_null(). jpayne@69: ** ^If the third parameter to sqlite3_bind_text() is not NULL, then jpayne@69: ** it should be a pointer to well-formed UTF8 text. jpayne@69: ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then jpayne@69: ** it should be a pointer to well-formed UTF16 text. jpayne@69: ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then jpayne@69: ** it should be a pointer to a well-formed unicode string that is jpayne@69: ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 jpayne@69: ** otherwise. jpayne@69: ** jpayne@69: ** [[byte-order determination rules]] ^The byte-order of jpayne@69: ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) jpayne@69: ** found in first character, which is removed, or in the absence of a BOM jpayne@69: ** the byte order is the native byte order of the host jpayne@69: ** machine for sqlite3_bind_text16() or the byte order specified in jpayne@69: ** the 6th parameter for sqlite3_bind_text64().)^ jpayne@69: ** ^If UTF16 input text contains invalid unicode jpayne@69: ** characters, then SQLite might change those invalid characters jpayne@69: ** into the unicode replacement character: U+FFFD. jpayne@69: ** jpayne@69: ** ^(In those routines that have a fourth argument, its value is the jpayne@69: ** number of bytes in the parameter. To be clear: the value is the jpayne@69: ** number of bytes in the value, not the number of characters.)^ jpayne@69: ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() jpayne@69: ** is negative, then the length of the string is jpayne@69: ** the number of bytes up to the first zero terminator. jpayne@69: ** If the fourth parameter to sqlite3_bind_blob() is negative, then jpayne@69: ** the behavior is undefined. jpayne@69: ** If a non-negative fourth parameter is provided to sqlite3_bind_text() jpayne@69: ** or sqlite3_bind_text16() or sqlite3_bind_text64() then jpayne@69: ** that parameter must be the byte offset jpayne@69: ** where the NUL terminator would occur assuming the string were NUL jpayne@69: ** terminated. If any NUL characters occurs at byte offsets less than jpayne@69: ** the value of the fourth parameter then the resulting string value will jpayne@69: ** contain embedded NULs. The result of expressions involving strings jpayne@69: ** with embedded NULs is undefined. jpayne@69: ** jpayne@69: ** ^The fifth argument to the BLOB and string binding interfaces controls jpayne@69: ** or indicates the lifetime of the object referenced by the third parameter. jpayne@69: ** These three options exist: jpayne@69: ** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished jpayne@69: ** with it may be passed. ^It is called to dispose of the BLOB or string even jpayne@69: ** if the call to the bind API fails, except the destructor is not called if jpayne@69: ** the third parameter is a NULL pointer or the fourth parameter is negative. jpayne@69: ** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that jpayne@69: ** the application remains responsible for disposing of the object. ^In this jpayne@69: ** case, the object and the provided pointer to it must remain valid until jpayne@69: ** either the prepared statement is finalized or the same SQL parameter is jpayne@69: ** bound to something else, whichever occurs sooner. jpayne@69: ** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the jpayne@69: ** object is to be copied prior to the return from sqlite3_bind_*(). ^The jpayne@69: ** object and pointer to it must remain valid until then. ^SQLite will then jpayne@69: ** manage the lifetime of its private copy. jpayne@69: ** jpayne@69: ** ^The sixth argument to sqlite3_bind_text64() must be one of jpayne@69: ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] jpayne@69: ** to specify the encoding of the text in the third parameter. If jpayne@69: ** the sixth argument to sqlite3_bind_text64() is not one of the jpayne@69: ** allowed values shown above, or if the text encoding is different jpayne@69: ** from the encoding specified by the sixth parameter, then the behavior jpayne@69: ** is undefined. jpayne@69: ** jpayne@69: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that jpayne@69: ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory jpayne@69: ** (just an integer to hold its size) while it is being processed. jpayne@69: ** Zeroblobs are intended to serve as placeholders for BLOBs whose jpayne@69: ** content is later written using jpayne@69: ** [sqlite3_blob_open | incremental BLOB I/O] routines. jpayne@69: ** ^A negative value for the zeroblob results in a zero-length BLOB. jpayne@69: ** jpayne@69: ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in jpayne@69: ** [prepared statement] S to have an SQL value of NULL, but to also be jpayne@69: ** associated with the pointer P of type T. ^D is either a NULL pointer or jpayne@69: ** a pointer to a destructor function for P. ^SQLite will invoke the jpayne@69: ** destructor D with a single argument of P when it is finished using jpayne@69: ** P. The T parameter should be a static string, preferably a string jpayne@69: ** literal. The sqlite3_bind_pointer() routine is part of the jpayne@69: ** [pointer passing interface] added for SQLite 3.20.0. jpayne@69: ** jpayne@69: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer jpayne@69: ** for the [prepared statement] or with a prepared statement for which jpayne@69: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], jpayne@69: ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() jpayne@69: ** routine is passed a [prepared statement] that has been finalized, the jpayne@69: ** result is undefined and probably harmful. jpayne@69: ** jpayne@69: ** ^Bindings are not cleared by the [sqlite3_reset()] routine. jpayne@69: ** ^Unbound parameters are interpreted as NULL. jpayne@69: ** jpayne@69: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an jpayne@69: ** [error code] if anything goes wrong. jpayne@69: ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB jpayne@69: ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or jpayne@69: ** [SQLITE_MAX_LENGTH]. jpayne@69: ** ^[SQLITE_RANGE] is returned if the parameter jpayne@69: ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. jpayne@69: ** jpayne@69: ** See also: [sqlite3_bind_parameter_count()], jpayne@69: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); jpayne@69: SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, jpayne@69: void(*)(void*)); jpayne@69: SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); jpayne@69: SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); jpayne@69: SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); jpayne@69: SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); jpayne@69: SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); jpayne@69: SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); jpayne@69: SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, jpayne@69: void(*)(void*), unsigned char encoding); jpayne@69: SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); jpayne@69: SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); jpayne@69: SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Number Of SQL Parameters jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^This routine can be used to find the number of [SQL parameters] jpayne@69: ** in a [prepared statement]. SQL parameters are tokens of the jpayne@69: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as jpayne@69: ** placeholders for values that are [sqlite3_bind_blob | bound] jpayne@69: ** to the parameters at a later time. jpayne@69: ** jpayne@69: ** ^(This routine actually returns the index of the largest (rightmost) jpayne@69: ** parameter. For all forms except ?NNN, this will correspond to the jpayne@69: ** number of unique parameters. If parameters of the ?NNN form are used, jpayne@69: ** there may be gaps in the list.)^ jpayne@69: ** jpayne@69: ** See also: [sqlite3_bind_blob|sqlite3_bind()], jpayne@69: ** [sqlite3_bind_parameter_name()], and jpayne@69: ** [sqlite3_bind_parameter_index()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Name Of A Host Parameter jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_bind_parameter_name(P,N) interface returns jpayne@69: ** the name of the N-th [SQL parameter] in the [prepared statement] P. jpayne@69: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" jpayne@69: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" jpayne@69: ** respectively. jpayne@69: ** In other words, the initial ":" or "$" or "@" or "?" jpayne@69: ** is included as part of the name.)^ jpayne@69: ** ^Parameters of the form "?" without a following integer have no name jpayne@69: ** and are referred to as "nameless" or "anonymous parameters". jpayne@69: ** jpayne@69: ** ^The first host parameter has an index of 1, not 0. jpayne@69: ** jpayne@69: ** ^If the value N is out of range or if the N-th parameter is jpayne@69: ** nameless, then NULL is returned. ^The returned string is jpayne@69: ** always in UTF-8 encoding even if the named parameter was jpayne@69: ** originally specified as UTF-16 in [sqlite3_prepare16()], jpayne@69: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_bind_blob|sqlite3_bind()], jpayne@69: ** [sqlite3_bind_parameter_count()], and jpayne@69: ** [sqlite3_bind_parameter_index()]. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Index Of A Parameter With A Given Name jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^Return the index of an SQL parameter given its name. ^The jpayne@69: ** index value returned is suitable for use as the second jpayne@69: ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero jpayne@69: ** is returned if no matching parameter is found. ^The parameter jpayne@69: ** name must be given in UTF-8 even if the original statement jpayne@69: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or jpayne@69: ** [sqlite3_prepare16_v3()]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_bind_blob|sqlite3_bind()], jpayne@69: ** [sqlite3_bind_parameter_count()], and jpayne@69: ** [sqlite3_bind_parameter_name()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Reset All Bindings On A Prepared Statement jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset jpayne@69: ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. jpayne@69: ** ^Use this routine to reset all host parameters to NULL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Number Of Columns In A Result Set jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^Return the number of columns in the result set returned by the jpayne@69: ** [prepared statement]. ^If this routine returns 0, that means the jpayne@69: ** [prepared statement] returns no data (for example an [UPDATE]). jpayne@69: ** ^However, just because this routine returns a positive number does not jpayne@69: ** mean that one or more rows of data will be returned. ^A SELECT statement jpayne@69: ** will always have a positive sqlite3_column_count() but depending on the jpayne@69: ** WHERE clause constraints and the table content, it might return no rows. jpayne@69: ** jpayne@69: ** See also: [sqlite3_data_count()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Column Names In A Result Set jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^These routines return the name assigned to a particular column jpayne@69: ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() jpayne@69: ** interface returns a pointer to a zero-terminated UTF-8 string jpayne@69: ** and sqlite3_column_name16() returns a pointer to a zero-terminated jpayne@69: ** UTF-16 string. ^The first parameter is the [prepared statement] jpayne@69: ** that implements the [SELECT] statement. ^The second parameter is the jpayne@69: ** column number. ^The leftmost column is number 0. jpayne@69: ** jpayne@69: ** ^The returned string pointer is valid until either the [prepared statement] jpayne@69: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically jpayne@69: ** reprepared by the first call to [sqlite3_step()] for a particular run jpayne@69: ** or until the next call to jpayne@69: ** sqlite3_column_name() or sqlite3_column_name16() on the same column. jpayne@69: ** jpayne@69: ** ^If sqlite3_malloc() fails during the processing of either routine jpayne@69: ** (for example during a conversion from UTF-8 to UTF-16) then a jpayne@69: ** NULL pointer is returned. jpayne@69: ** jpayne@69: ** ^The name of a result column is the value of the "AS" clause for jpayne@69: ** that column, if there is an AS clause. If there is no AS clause jpayne@69: ** then the name of the column is unspecified and may change from jpayne@69: ** one release of SQLite to the next. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); jpayne@69: SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Source Of Data In A Query Result jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^These routines provide a means to determine the database, table, and jpayne@69: ** table column that is the origin of a particular result column in jpayne@69: ** [SELECT] statement. jpayne@69: ** ^The name of the database or table or column can be returned as jpayne@69: ** either a UTF-8 or UTF-16 string. ^The _database_ routines return jpayne@69: ** the database name, the _table_ routines return the table name, and jpayne@69: ** the origin_ routines return the column name. jpayne@69: ** ^The returned string is valid until the [prepared statement] is destroyed jpayne@69: ** using [sqlite3_finalize()] or until the statement is automatically jpayne@69: ** reprepared by the first call to [sqlite3_step()] for a particular run jpayne@69: ** or until the same information is requested jpayne@69: ** again in a different encoding. jpayne@69: ** jpayne@69: ** ^The names returned are the original un-aliased names of the jpayne@69: ** database, table, and column. jpayne@69: ** jpayne@69: ** ^The first argument to these interfaces is a [prepared statement]. jpayne@69: ** ^These functions return information about the Nth result column returned by jpayne@69: ** the statement, where N is the second function argument. jpayne@69: ** ^The left-most column is column 0 for these routines. jpayne@69: ** jpayne@69: ** ^If the Nth column returned by the statement is an expression or jpayne@69: ** subquery and is not a column value, then all of these functions return jpayne@69: ** NULL. ^These routines might also return NULL if a memory allocation error jpayne@69: ** occurs. ^Otherwise, they return the name of the attached database, table, jpayne@69: ** or column that query result column was extracted from. jpayne@69: ** jpayne@69: ** ^As with all other SQLite APIs, those whose names end with "16" return jpayne@69: ** UTF-16 encoded strings and the other functions return UTF-8. jpayne@69: ** jpayne@69: ** ^These APIs are only available if the library was compiled with the jpayne@69: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. jpayne@69: ** jpayne@69: ** If two or more threads call one or more jpayne@69: ** [sqlite3_column_database_name | column metadata interfaces] jpayne@69: ** for the same [prepared statement] and result column jpayne@69: ** at the same time then the results are undefined. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); jpayne@69: SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); jpayne@69: SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); jpayne@69: SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); jpayne@69: SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); jpayne@69: SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Declared Datatype Of A Query Result jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^(The first parameter is a [prepared statement]. jpayne@69: ** If this statement is a [SELECT] statement and the Nth column of the jpayne@69: ** returned result set of that [SELECT] is a table column (not an jpayne@69: ** expression or subquery) then the declared type of the table jpayne@69: ** column is returned.)^ ^If the Nth column of the result set is an jpayne@69: ** expression or subquery, then a NULL pointer is returned. jpayne@69: ** ^The returned string is always UTF-8 encoded. jpayne@69: ** jpayne@69: ** ^(For example, given the database schema: jpayne@69: ** jpayne@69: ** CREATE TABLE t1(c1 VARIANT); jpayne@69: ** jpayne@69: ** and the following statement to be compiled: jpayne@69: ** jpayne@69: ** SELECT c1 + 1, c1 FROM t1; jpayne@69: ** jpayne@69: ** this routine would return the string "VARIANT" for the second result jpayne@69: ** column (i==1), and a NULL pointer for the first result column (i==0).)^ jpayne@69: ** jpayne@69: ** ^SQLite uses dynamic run-time typing. ^So just because a column jpayne@69: ** is declared to contain a particular type does not mean that the jpayne@69: ** data stored in that column is of the declared type. SQLite is jpayne@69: ** strongly typed, but the typing is dynamic not static. ^Type jpayne@69: ** is associated with individual values, not with the containers jpayne@69: ** used to hold those values. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); jpayne@69: SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Evaluate An SQL Statement jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** After a [prepared statement] has been prepared using any of jpayne@69: ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], jpayne@69: ** or [sqlite3_prepare16_v3()] or one of the legacy jpayne@69: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function jpayne@69: ** must be called one or more times to evaluate the statement. jpayne@69: ** jpayne@69: ** The details of the behavior of the sqlite3_step() interface depend jpayne@69: ** on whether the statement was prepared using the newer "vX" interfaces jpayne@69: ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], jpayne@69: ** [sqlite3_prepare16_v2()] or the older legacy jpayne@69: ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the jpayne@69: ** new "vX" interface is recommended for new applications but the legacy jpayne@69: ** interface will continue to be supported. jpayne@69: ** jpayne@69: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], jpayne@69: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. jpayne@69: ** ^With the "v2" interface, any of the other [result codes] or jpayne@69: ** [extended result codes] might be returned as well. jpayne@69: ** jpayne@69: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the jpayne@69: ** database locks it needs to do its job. ^If the statement is a [COMMIT] jpayne@69: ** or occurs outside of an explicit transaction, then you can retry the jpayne@69: ** statement. If the statement is not a [COMMIT] and occurs within an jpayne@69: ** explicit transaction then you should rollback the transaction before jpayne@69: ** continuing. jpayne@69: ** jpayne@69: ** ^[SQLITE_DONE] means that the statement has finished executing jpayne@69: ** successfully. sqlite3_step() should not be called again on this virtual jpayne@69: ** machine without first calling [sqlite3_reset()] to reset the virtual jpayne@69: ** machine back to its initial state. jpayne@69: ** jpayne@69: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] jpayne@69: ** is returned each time a new row of data is ready for processing by the jpayne@69: ** caller. The values may be accessed using the [column access functions]. jpayne@69: ** sqlite3_step() is called again to retrieve the next row of data. jpayne@69: ** jpayne@69: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint jpayne@69: ** violation) has occurred. sqlite3_step() should not be called again on jpayne@69: ** the VM. More information may be found by calling [sqlite3_errmsg()]. jpayne@69: ** ^With the legacy interface, a more specific error code (for example, jpayne@69: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) jpayne@69: ** can be obtained by calling [sqlite3_reset()] on the jpayne@69: ** [prepared statement]. ^In the "v2" interface, jpayne@69: ** the more specific error code is returned directly by sqlite3_step(). jpayne@69: ** jpayne@69: ** [SQLITE_MISUSE] means that the this routine was called inappropriately. jpayne@69: ** Perhaps it was called on a [prepared statement] that has jpayne@69: ** already been [sqlite3_finalize | finalized] or on one that had jpayne@69: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could jpayne@69: ** be the case that the same database connection is being used by two or jpayne@69: ** more threads at the same moment in time. jpayne@69: ** jpayne@69: ** For all versions of SQLite up to and including 3.6.23.1, a call to jpayne@69: ** [sqlite3_reset()] was required after sqlite3_step() returned anything jpayne@69: ** other than [SQLITE_ROW] before any subsequent invocation of jpayne@69: ** sqlite3_step(). Failure to reset the prepared statement using jpayne@69: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from jpayne@69: ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], jpayne@69: ** sqlite3_step() began jpayne@69: ** calling [sqlite3_reset()] automatically in this circumstance rather jpayne@69: ** than returning [SQLITE_MISUSE]. This is not considered a compatibility jpayne@69: ** break because any application that ever receives an SQLITE_MISUSE error jpayne@69: ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option jpayne@69: ** can be used to restore the legacy behavior. jpayne@69: ** jpayne@69: ** Goofy Interface Alert: In the legacy interface, the sqlite3_step() jpayne@69: ** API always returns a generic error code, [SQLITE_ERROR], following any jpayne@69: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call jpayne@69: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the jpayne@69: ** specific [error codes] that better describes the error. jpayne@69: ** We admit that this is a goofy design. The problem has been fixed jpayne@69: ** with the "v2" interface. If you prepare all of your SQL statements jpayne@69: ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] jpayne@69: ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead jpayne@69: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, jpayne@69: ** then the more specific [error codes] are returned directly jpayne@69: ** by sqlite3_step(). The use of the "vX" interfaces is recommended. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_step(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Number of columns in a result set jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_data_count(P) interface returns the number of columns in the jpayne@69: ** current row of the result set of [prepared statement] P. jpayne@69: ** ^If prepared statement P does not have results ready to return jpayne@69: ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of jpayne@69: ** interfaces) then sqlite3_data_count(P) returns 0. jpayne@69: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. jpayne@69: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to jpayne@69: ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) jpayne@69: ** will return non-zero if previous call to [sqlite3_step](P) returned jpayne@69: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] jpayne@69: ** where it always returns zero since each step of that multi-step jpayne@69: ** pragma returns 0 columns of data. jpayne@69: ** jpayne@69: ** See also: [sqlite3_column_count()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Fundamental Datatypes jpayne@69: ** KEYWORDS: SQLITE_TEXT jpayne@69: ** jpayne@69: ** ^(Every value in SQLite has one of five fundamental datatypes: jpayne@69: ** jpayne@69: ** )^ jpayne@69: ** jpayne@69: ** These constants are codes for each of those types. jpayne@69: ** jpayne@69: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 jpayne@69: ** for a completely different meaning. Software that links against both jpayne@69: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not jpayne@69: ** SQLITE_TEXT. jpayne@69: */ jpayne@69: #define SQLITE_INTEGER 1 jpayne@69: #define SQLITE_FLOAT 2 jpayne@69: #define SQLITE_BLOB 4 jpayne@69: #define SQLITE_NULL 5 jpayne@69: #ifdef SQLITE_TEXT jpayne@69: # undef SQLITE_TEXT jpayne@69: #else jpayne@69: # define SQLITE_TEXT 3 jpayne@69: #endif jpayne@69: #define SQLITE3_TEXT 3 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Result Values From A Query jpayne@69: ** KEYWORDS: {column access functions} jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** Summary: jpayne@69: **
jpayne@69: **
sqlite3_column_blob→BLOB result jpayne@69: **
sqlite3_column_double→REAL result jpayne@69: **
sqlite3_column_int→32-bit INTEGER result jpayne@69: **
sqlite3_column_int64→64-bit INTEGER result jpayne@69: **
sqlite3_column_text→UTF-8 TEXT result jpayne@69: **
sqlite3_column_text16→UTF-16 TEXT result jpayne@69: **
sqlite3_column_value→The result as an jpayne@69: ** [sqlite3_value|unprotected sqlite3_value] object. jpayne@69: **
    jpayne@69: **
sqlite3_column_bytes→Size of a BLOB jpayne@69: ** or a UTF-8 TEXT result in bytes jpayne@69: **
sqlite3_column_bytes16   jpayne@69: ** →  Size of UTF-16 jpayne@69: ** TEXT in bytes jpayne@69: **
sqlite3_column_type→Default jpayne@69: ** datatype of the result jpayne@69: **
jpayne@69: ** jpayne@69: ** Details: jpayne@69: ** jpayne@69: ** ^These routines return information about a single column of the current jpayne@69: ** result row of a query. ^In every case the first argument is a pointer jpayne@69: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] jpayne@69: ** that was returned from [sqlite3_prepare_v2()] or one of its variants) jpayne@69: ** and the second argument is the index of the column for which information jpayne@69: ** should be returned. ^The leftmost column of the result set has the index 0. jpayne@69: ** ^The number of columns in the result can be determined using jpayne@69: ** [sqlite3_column_count()]. jpayne@69: ** jpayne@69: ** If the SQL statement does not currently point to a valid row, or if the jpayne@69: ** column index is out of range, the result is undefined. jpayne@69: ** These routines may only be called when the most recent call to jpayne@69: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither jpayne@69: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. jpayne@69: ** If any of these routines are called after [sqlite3_reset()] or jpayne@69: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned jpayne@69: ** something other than [SQLITE_ROW], the results are undefined. jpayne@69: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] jpayne@69: ** are called from a different thread while any of these routines jpayne@69: ** are pending, then the results are undefined. jpayne@69: ** jpayne@69: ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) jpayne@69: ** each return the value of a result column in a specific data format. If jpayne@69: ** the result column is not initially in the requested format (for example, jpayne@69: ** if the query returns an integer but the sqlite3_column_text() interface jpayne@69: ** is used to extract the value) then an automatic type conversion is performed. jpayne@69: ** jpayne@69: ** ^The sqlite3_column_type() routine returns the jpayne@69: ** [SQLITE_INTEGER | datatype code] for the initial data type jpayne@69: ** of the result column. ^The returned value is one of [SQLITE_INTEGER], jpayne@69: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. jpayne@69: ** The return value of sqlite3_column_type() can be used to decide which jpayne@69: ** of the first six interface should be used to extract the column value. jpayne@69: ** The value returned by sqlite3_column_type() is only meaningful if no jpayne@69: ** automatic type conversions have occurred for the value in question. jpayne@69: ** After a type conversion, the result of calling sqlite3_column_type() jpayne@69: ** is undefined, though harmless. Future jpayne@69: ** versions of SQLite may change the behavior of sqlite3_column_type() jpayne@69: ** following a type conversion. jpayne@69: ** jpayne@69: ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() jpayne@69: ** or sqlite3_column_bytes16() interfaces can be used to determine the size jpayne@69: ** of that BLOB or string. jpayne@69: ** jpayne@69: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() jpayne@69: ** routine returns the number of bytes in that BLOB or string. jpayne@69: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts jpayne@69: ** the string to UTF-8 and then returns the number of bytes. jpayne@69: ** ^If the result is a numeric value then sqlite3_column_bytes() uses jpayne@69: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns jpayne@69: ** the number of bytes in that string. jpayne@69: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. jpayne@69: ** jpayne@69: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() jpayne@69: ** routine returns the number of bytes in that BLOB or string. jpayne@69: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts jpayne@69: ** the string to UTF-16 and then returns the number of bytes. jpayne@69: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses jpayne@69: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns jpayne@69: ** the number of bytes in that string. jpayne@69: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. jpayne@69: ** jpayne@69: ** ^The values returned by [sqlite3_column_bytes()] and jpayne@69: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end jpayne@69: ** of the string. ^For clarity: the values returned by jpayne@69: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of jpayne@69: ** bytes in the string, not the number of characters. jpayne@69: ** jpayne@69: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), jpayne@69: ** even empty strings, are always zero-terminated. ^The return jpayne@69: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. jpayne@69: ** jpayne@69: ** ^Strings returned by sqlite3_column_text16() always have the endianness jpayne@69: ** which is native to the platform, regardless of the text encoding set jpayne@69: ** for the database. jpayne@69: ** jpayne@69: ** Warning: ^The object returned by [sqlite3_column_value()] is an jpayne@69: ** [unprotected sqlite3_value] object. In a multithreaded environment, jpayne@69: ** an unprotected sqlite3_value object may only be used safely with jpayne@69: ** [sqlite3_bind_value()] and [sqlite3_result_value()]. jpayne@69: ** If the [unprotected sqlite3_value] object returned by jpayne@69: ** [sqlite3_column_value()] is used in any other way, including calls jpayne@69: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], jpayne@69: ** or [sqlite3_value_bytes()], the behavior is not threadsafe. jpayne@69: ** Hence, the sqlite3_column_value() interface jpayne@69: ** is normally only useful within the implementation of jpayne@69: ** [application-defined SQL functions] or [virtual tables], not within jpayne@69: ** top-level application code. jpayne@69: ** jpayne@69: ** These routines may attempt to convert the datatype of the result. jpayne@69: ** ^For example, if the internal representation is FLOAT and a text result jpayne@69: ** is requested, [sqlite3_snprintf()] is used internally to perform the jpayne@69: ** conversion automatically. ^(The following table details the conversions jpayne@69: ** that are applied: jpayne@69: ** jpayne@69: **
jpayne@69: ** jpayne@69: **
Internal
Type 		Requested
Type 		Conversion jpayne@69: ** jpayne@69: **
NULL INTEGER Result is 0 jpayne@69: **
NULL FLOAT Result is 0.0 jpayne@69: **
NULL TEXT Result is a NULL pointer jpayne@69: **
NULL BLOB Result is a NULL pointer jpayne@69: **
INTEGER FLOAT Convert from integer to float jpayne@69: **
INTEGER TEXT ASCII rendering of the integer jpayne@69: **
INTEGER BLOB Same as INTEGER->TEXT jpayne@69: **
FLOAT INTEGER [CAST] to INTEGER jpayne@69: **
FLOAT TEXT ASCII rendering of the float jpayne@69: **
FLOAT BLOB [CAST] to BLOB jpayne@69: **
TEXT INTEGER [CAST] to INTEGER jpayne@69: **
TEXT FLOAT [CAST] to REAL jpayne@69: **
TEXT BLOB No change jpayne@69: **
BLOB INTEGER [CAST] to INTEGER jpayne@69: **
BLOB FLOAT [CAST] to REAL jpayne@69: **
BLOB TEXT [CAST] to TEXT, ensure zero terminator jpayne@69: **
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** Note that when type conversions occur, pointers returned by prior jpayne@69: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or jpayne@69: ** sqlite3_column_text16() may be invalidated. jpayne@69: ** Type conversions and pointer invalidations might occur jpayne@69: ** in the following cases: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do jpayne@69: ** not invalidate a prior pointer, though of course the content of the buffer jpayne@69: ** that the prior pointer references will have been modified. Other kinds jpayne@69: ** of conversion are done in place when it is possible, but sometimes they jpayne@69: ** are not possible and in those cases prior pointers are invalidated. jpayne@69: ** jpayne@69: ** The safest policy is to invoke these routines jpayne@69: ** in one of the following ways: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** In other words, you should call sqlite3_column_text(), jpayne@69: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result jpayne@69: ** into the desired format, then invoke sqlite3_column_bytes() or jpayne@69: ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls jpayne@69: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to jpayne@69: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() jpayne@69: ** with calls to sqlite3_column_bytes(). jpayne@69: ** jpayne@69: ** ^The pointers returned are valid until a type conversion occurs as jpayne@69: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or jpayne@69: ** [sqlite3_finalize()] is called. ^The memory space used to hold strings jpayne@69: ** and BLOBs is freed automatically. Do not pass the pointers returned jpayne@69: ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into jpayne@69: ** [sqlite3_free()]. jpayne@69: ** jpayne@69: ** As long as the input parameters are correct, these routines will only jpayne@69: ** fail if an out-of-memory error occurs during a format conversion. jpayne@69: ** Only the following subset of interfaces are subject to out-of-memory jpayne@69: ** errors: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** If an out-of-memory error occurs, then the return value from these jpayne@69: ** routines is the same as if the column had contained an SQL NULL value. jpayne@69: ** Valid SQL NULL returns can be distinguished from out-of-memory errors jpayne@69: ** by invoking the [sqlite3_errcode()] immediately after the suspect jpayne@69: ** return value is obtained and before any jpayne@69: ** other SQLite interface is called on the same [database connection]. jpayne@69: */ jpayne@69: SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); jpayne@69: SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Destroy A Prepared Statement Object jpayne@69: ** DESTRUCTOR: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. jpayne@69: ** ^If the most recent evaluation of the statement encountered no errors jpayne@69: ** or if the statement is never been evaluated, then sqlite3_finalize() returns jpayne@69: ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then jpayne@69: ** sqlite3_finalize(S) returns the appropriate [error code] or jpayne@69: ** [extended error code]. jpayne@69: ** jpayne@69: ** ^The sqlite3_finalize(S) routine can be called at any point during jpayne@69: ** the life cycle of [prepared statement] S: jpayne@69: ** before statement S is ever evaluated, after jpayne@69: ** one or more calls to [sqlite3_reset()], or after any call jpayne@69: ** to [sqlite3_step()] regardless of whether or not the statement has jpayne@69: ** completed execution. jpayne@69: ** jpayne@69: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. jpayne@69: ** jpayne@69: ** The application must finalize every [prepared statement] in order to avoid jpayne@69: ** resource leaks. It is a grievous error for the application to try to use jpayne@69: ** a prepared statement after it has been finalized. Any use of a prepared jpayne@69: ** statement after it has been finalized can result in undefined and jpayne@69: ** undesirable behavior such as segfaults and heap corruption. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Reset A Prepared Statement Object jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** The sqlite3_reset() function is called to reset a [prepared statement] jpayne@69: ** object back to its initial state, ready to be re-executed. jpayne@69: ** ^Any SQL statement variables that had values bound to them using jpayne@69: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. jpayne@69: ** Use [sqlite3_clear_bindings()] to reset the bindings. jpayne@69: ** jpayne@69: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S jpayne@69: ** back to the beginning of its program. jpayne@69: ** jpayne@69: ** ^The return code from [sqlite3_reset(S)] indicates whether or not jpayne@69: ** the previous evaluation of prepared statement S completed successfully. jpayne@69: ** ^If [sqlite3_step(S)] has never before been called on S or if jpayne@69: ** [sqlite3_step(S)] has not been called since the previous call jpayne@69: ** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return jpayne@69: ** [SQLITE_OK]. jpayne@69: ** jpayne@69: ** ^If the most recent call to [sqlite3_step(S)] for the jpayne@69: ** [prepared statement] S indicated an error, then jpayne@69: ** [sqlite3_reset(S)] returns an appropriate [error code]. jpayne@69: ** ^The [sqlite3_reset(S)] interface might also return an [error code] jpayne@69: ** if there were no prior errors but the process of resetting jpayne@69: ** the prepared statement caused a new error. ^For example, if an jpayne@69: ** [INSERT] statement with a [RETURNING] clause is only stepped one time, jpayne@69: ** that one call to [sqlite3_step(S)] might return SQLITE_ROW but jpayne@69: ** the overall statement might still fail and the [sqlite3_reset(S)] call jpayne@69: ** might return SQLITE_BUSY if locking constraints prevent the jpayne@69: ** database change from committing. Therefore, it is important that jpayne@69: ** applications check the return code from [sqlite3_reset(S)] even if jpayne@69: ** no prior call to [sqlite3_step(S)] indicated a problem. jpayne@69: ** jpayne@69: ** ^The [sqlite3_reset(S)] interface does not change the values jpayne@69: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create Or Redefine SQL Functions jpayne@69: ** KEYWORDS: {function creation routines} jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These functions (collectively known as "function creation routines") jpayne@69: ** are used to add SQL functions or aggregates or to redefine the behavior jpayne@69: ** of existing SQL functions or aggregates. The only differences between jpayne@69: ** the three "sqlite3_create_function*" routines are the text encoding jpayne@69: ** expected for the second parameter (the name of the function being jpayne@69: ** created) and the presence or absence of a destructor callback for jpayne@69: ** the application data pointer. Function sqlite3_create_window_function() jpayne@69: ** is similar, but allows the user to supply the extra callback functions jpayne@69: ** needed by [aggregate window functions]. jpayne@69: ** jpayne@69: ** ^The first parameter is the [database connection] to which the SQL jpayne@69: ** function is to be added. ^If an application uses more than one database jpayne@69: ** connection then application-defined SQL functions must be added jpayne@69: ** to each database connection separately. jpayne@69: ** jpayne@69: ** ^The second parameter is the name of the SQL function to be created or jpayne@69: ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 jpayne@69: ** representation, exclusive of the zero-terminator. ^Note that the name jpayne@69: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. jpayne@69: ** ^Any attempt to create a function with a longer name jpayne@69: ** will result in [SQLITE_MISUSE] being returned. jpayne@69: ** jpayne@69: ** ^The third parameter (nArg) jpayne@69: ** is the number of arguments that the SQL function or jpayne@69: ** aggregate takes. ^If this parameter is -1, then the SQL function or jpayne@69: ** aggregate may take any number of arguments between 0 and the limit jpayne@69: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third jpayne@69: ** parameter is less than -1 or greater than 127 then the behavior is jpayne@69: ** undefined. jpayne@69: ** jpayne@69: ** ^The fourth parameter, eTextRep, specifies what jpayne@69: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for jpayne@69: ** its parameters. The application should set this parameter to jpayne@69: ** [SQLITE_UTF16LE] if the function implementation invokes jpayne@69: ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the jpayne@69: ** implementation invokes [sqlite3_value_text16be()] on an input, or jpayne@69: ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] jpayne@69: ** otherwise. ^The same SQL function may be registered multiple times using jpayne@69: ** different preferred text encodings, with different implementations for jpayne@69: ** each encoding. jpayne@69: ** ^When multiple implementations of the same function are available, SQLite jpayne@69: ** will pick the one that involves the least amount of data conversion. jpayne@69: ** jpayne@69: ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] jpayne@69: ** to signal that the function will always return the same result given jpayne@69: ** the same inputs within a single SQL statement. Most SQL functions are jpayne@69: ** deterministic. The built-in [random()] SQL function is an example of a jpayne@69: ** function that is not deterministic. The SQLite query planner is able to jpayne@69: ** perform additional optimizations on deterministic functions, so use jpayne@69: ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. jpayne@69: ** jpayne@69: ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] jpayne@69: ** flag, which if present prevents the function from being invoked from jpayne@69: ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, jpayne@69: ** index expressions, or the WHERE clause of partial indexes. jpayne@69: ** jpayne@69: ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for jpayne@69: ** all application-defined SQL functions that do not need to be jpayne@69: ** used inside of triggers, view, CHECK constraints, or other elements of jpayne@69: ** the database schema. This flags is especially recommended for SQL jpayne@69: ** functions that have side effects or reveal internal application state. jpayne@69: ** Without this flag, an attacker might be able to modify the schema of jpayne@69: ** a database file to include invocations of the function with parameters jpayne@69: ** chosen by the attacker, which the application will then execute when jpayne@69: ** the database file is opened and read. jpayne@69: ** jpayne@69: ** ^(The fifth parameter is an arbitrary pointer. The implementation of the jpayne@69: ** function can gain access to this pointer using [sqlite3_user_data()].)^ jpayne@69: ** jpayne@69: ** ^The sixth, seventh and eighth parameters passed to the three jpayne@69: ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are jpayne@69: ** pointers to C-language functions that implement the SQL function or jpayne@69: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc jpayne@69: ** callback only; NULL pointers must be passed as the xStep and xFinal jpayne@69: ** parameters. ^An aggregate SQL function requires an implementation of xStep jpayne@69: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing jpayne@69: ** SQL function or aggregate, pass NULL pointers for all three function jpayne@69: ** callbacks. jpayne@69: ** jpayne@69: ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue jpayne@69: ** and xInverse) passed to sqlite3_create_window_function are pointers to jpayne@69: ** C-language callbacks that implement the new function. xStep and xFinal jpayne@69: ** must both be non-NULL. xValue and xInverse may either both be NULL, in jpayne@69: ** which case a regular aggregate function is created, or must both be jpayne@69: ** non-NULL, in which case the new function may be used as either an aggregate jpayne@69: ** or aggregate window function. More details regarding the implementation jpayne@69: ** of aggregate window functions are jpayne@69: ** [user-defined window functions|available here]. jpayne@69: ** jpayne@69: ** ^(If the final parameter to sqlite3_create_function_v2() or jpayne@69: ** sqlite3_create_window_function() is not NULL, then it is destructor for jpayne@69: ** the application data pointer. The destructor is invoked when the function jpayne@69: ** is deleted, either by being overloaded or when the database connection jpayne@69: ** closes.)^ ^The destructor is also invoked if the call to jpayne@69: ** sqlite3_create_function_v2() fails. ^When the destructor callback is jpayne@69: ** invoked, it is passed a single argument which is a copy of the application jpayne@69: ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). jpayne@69: ** jpayne@69: ** ^It is permitted to register multiple implementations of the same jpayne@69: ** functions with the same name but with either differing numbers of jpayne@69: ** arguments or differing preferred text encodings. ^SQLite will use jpayne@69: ** the implementation that most closely matches the way in which the jpayne@69: ** SQL function is used. ^A function implementation with a non-negative jpayne@69: ** nArg parameter is a better match than a function implementation with jpayne@69: ** a negative nArg. ^A function where the preferred text encoding jpayne@69: ** matches the database encoding is a better jpayne@69: ** match than a function where the encoding is different. jpayne@69: ** ^A function where the encoding difference is between UTF16le and UTF16be jpayne@69: ** is a closer match than a function where the encoding difference is jpayne@69: ** between UTF8 and UTF16. jpayne@69: ** jpayne@69: ** ^Built-in functions may be overloaded by new application-defined functions. jpayne@69: ** jpayne@69: ** ^An application-defined function is permitted to call other jpayne@69: ** SQLite interfaces. However, such calls must not jpayne@69: ** close the database connection nor finalize or reset the prepared jpayne@69: ** statement in which the function is running. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_create_function( jpayne@69: sqlite3 *db, jpayne@69: const char *zFunctionName, jpayne@69: int nArg, jpayne@69: int eTextRep, jpayne@69: void *pApp, jpayne@69: void (*xFunc)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xStep)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xFinal)(sqlite3_context*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_function16( jpayne@69: sqlite3 *db, jpayne@69: const void *zFunctionName, jpayne@69: int nArg, jpayne@69: int eTextRep, jpayne@69: void *pApp, jpayne@69: void (*xFunc)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xStep)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xFinal)(sqlite3_context*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_function_v2( jpayne@69: sqlite3 *db, jpayne@69: const char *zFunctionName, jpayne@69: int nArg, jpayne@69: int eTextRep, jpayne@69: void *pApp, jpayne@69: void (*xFunc)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xStep)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xFinal)(sqlite3_context*), jpayne@69: void(*xDestroy)(void*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_window_function( jpayne@69: sqlite3 *db, jpayne@69: const char *zFunctionName, jpayne@69: int nArg, jpayne@69: int eTextRep, jpayne@69: void *pApp, jpayne@69: void (*xStep)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void (*xFinal)(sqlite3_context*), jpayne@69: void (*xValue)(sqlite3_context*), jpayne@69: void (*xInverse)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void(*xDestroy)(void*) jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Text Encodings jpayne@69: ** jpayne@69: ** These constant define integer codes that represent the various jpayne@69: ** text encodings supported by SQLite. jpayne@69: */ jpayne@69: #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ jpayne@69: #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ jpayne@69: #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ jpayne@69: #define SQLITE_UTF16 4 /* Use native byte order */ jpayne@69: #define SQLITE_ANY 5 /* Deprecated */ jpayne@69: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Function Flags jpayne@69: ** jpayne@69: ** These constants may be ORed together with the jpayne@69: ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument jpayne@69: ** to [sqlite3_create_function()], [sqlite3_create_function16()], or jpayne@69: ** [sqlite3_create_function_v2()]. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_DETERMINISTIC]]
SQLITE_DETERMINISTIC
jpayne@69: ** The SQLITE_DETERMINISTIC flag means that the new function always gives jpayne@69: ** the same output when the input parameters are the same. jpayne@69: ** The [abs|abs() function] is deterministic, for example, but jpayne@69: ** [randomblob|randomblob()] is not. Functions must jpayne@69: ** be deterministic in order to be used in certain contexts such as jpayne@69: ** with the WHERE clause of [partial indexes] or in [generated columns]. jpayne@69: ** SQLite might also optimize deterministic functions by factoring them jpayne@69: ** out of inner loops. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DIRECTONLY]]
SQLITE_DIRECTONLY
jpayne@69: ** The SQLITE_DIRECTONLY flag means that the function may only be invoked jpayne@69: ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in jpayne@69: ** schema structures such as [CHECK constraints], [DEFAULT clauses], jpayne@69: ** [expression indexes], [partial indexes], or [generated columns]. jpayne@69: **

jpayne@69: ** The SQLITE_DIRECTONLY flag is recommended for any jpayne@69: ** [application-defined SQL function] jpayne@69: ** that has side-effects or that could potentially leak sensitive information. jpayne@69: ** This will prevent attacks in which an application is tricked jpayne@69: ** into using a database file that has had its schema surreptitiously jpayne@69: ** modified to invoke the application-defined function in ways that are jpayne@69: ** harmful. jpayne@69: **

jpayne@69: ** Some people say it is good practice to set SQLITE_DIRECTONLY on all jpayne@69: ** [application-defined SQL functions], regardless of whether or not they jpayne@69: ** are security sensitive, as doing so prevents those functions from being used jpayne@69: ** inside of the database schema, and thus ensures that the database jpayne@69: ** can be inspected and modified using generic tools (such as the [CLI]) jpayne@69: ** that do not have access to the application-defined functions. jpayne@69: **

jpayne@69: ** jpayne@69: ** [[SQLITE_INNOCUOUS]]
SQLITE_INNOCUOUS
jpayne@69: ** The SQLITE_INNOCUOUS flag means that the function is unlikely jpayne@69: ** to cause problems even if misused. An innocuous function should have jpayne@69: ** no side effects and should not depend on any values other than its jpayne@69: ** input parameters. The [abs|abs() function] is an example of an jpayne@69: ** innocuous function. jpayne@69: ** The [load_extension() SQL function] is not innocuous because of its jpayne@69: ** side effects. jpayne@69: **

SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not jpayne@69: ** exactly the same. The [random|random() function] is an example of a jpayne@69: ** function that is innocuous but not deterministic. jpayne@69: **

Some heightened security settings jpayne@69: ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) jpayne@69: ** disable the use of SQL functions inside views and triggers and in jpayne@69: ** schema structures such as [CHECK constraints], [DEFAULT clauses], jpayne@69: ** [expression indexes], [partial indexes], and [generated columns] unless jpayne@69: ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions jpayne@69: ** are innocuous. Developers are advised to avoid using the jpayne@69: ** SQLITE_INNOCUOUS flag for application-defined functions unless the jpayne@69: ** function has been carefully audited and found to be free of potentially jpayne@69: ** security-adverse side-effects and information-leaks. jpayne@69: **

jpayne@69: ** jpayne@69: ** [[SQLITE_SUBTYPE]]
SQLITE_SUBTYPE
jpayne@69: ** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call jpayne@69: ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. jpayne@69: ** This flag instructs SQLite to omit some corner-case optimizations that jpayne@69: ** might disrupt the operation of the [sqlite3_value_subtype()] function, jpayne@69: ** causing it to return zero rather than the correct subtype(). jpayne@69: ** SQL functions that invokes [sqlite3_value_subtype()] should have this jpayne@69: ** property. If the SQLITE_SUBTYPE property is omitted, then the return jpayne@69: ** value from [sqlite3_value_subtype()] might sometimes be zero even though jpayne@69: ** a non-zero subtype was specified by the function argument expression. jpayne@69: ** jpayne@69: ** [[SQLITE_RESULT_SUBTYPE]]
SQLITE_RESULT_SUBTYPE
jpayne@69: ** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call jpayne@69: ** [sqlite3_result_subtype()] to cause a sub-type to be associated with its jpayne@69: ** result. jpayne@69: ** Every function that invokes [sqlite3_result_subtype()] should have this jpayne@69: ** property. If it does not, then the call to [sqlite3_result_subtype()] jpayne@69: ** might become a no-op if the function is used as term in an jpayne@69: ** [expression index]. On the other hand, SQL functions that never invoke jpayne@69: ** [sqlite3_result_subtype()] should avoid setting this property, as the jpayne@69: ** purpose of this property is to disable certain optimizations that are jpayne@69: ** incompatible with subtypes. jpayne@69: **
jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_DETERMINISTIC 0x000000800 jpayne@69: #define SQLITE_DIRECTONLY 0x000080000 jpayne@69: #define SQLITE_SUBTYPE 0x000100000 jpayne@69: #define SQLITE_INNOCUOUS 0x000200000 jpayne@69: #define SQLITE_RESULT_SUBTYPE 0x001000000 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Deprecated Functions jpayne@69: ** DEPRECATED jpayne@69: ** jpayne@69: ** These functions are [deprecated]. In order to maintain jpayne@69: ** backwards compatibility with older code, these functions continue jpayne@69: ** to be supported. However, new applications should avoid jpayne@69: ** the use of these functions. To encourage programmers to avoid jpayne@69: ** these functions, we will not explain what they do. jpayne@69: */ jpayne@69: #ifndef SQLITE_OMIT_DEPRECATED jpayne@69: SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); jpayne@69: SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); jpayne@69: SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); jpayne@69: SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); jpayne@69: SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); jpayne@69: SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), jpayne@69: void*,sqlite3_int64); jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtaining SQL Values jpayne@69: ** METHOD: sqlite3_value jpayne@69: ** jpayne@69: ** Summary: jpayne@69: **
jpayne@69: **
sqlite3_value_blob→BLOB value jpayne@69: **
sqlite3_value_double→REAL value jpayne@69: **
sqlite3_value_int→32-bit INTEGER value jpayne@69: **
sqlite3_value_int64→64-bit INTEGER value jpayne@69: **
sqlite3_value_pointer→Pointer value jpayne@69: **
sqlite3_value_text→UTF-8 TEXT value jpayne@69: **
sqlite3_value_text16→UTF-16 TEXT value in jpayne@69: ** the native byteorder jpayne@69: **
sqlite3_value_text16be→UTF-16be TEXT value jpayne@69: **
sqlite3_value_text16le→UTF-16le TEXT value jpayne@69: **
    jpayne@69: **
sqlite3_value_bytes→Size of a BLOB jpayne@69: ** or a UTF-8 TEXT in bytes jpayne@69: **
sqlite3_value_bytes16   jpayne@69: ** →  Size of UTF-16 jpayne@69: ** TEXT in bytes jpayne@69: **
sqlite3_value_type→Default jpayne@69: ** datatype of the value jpayne@69: **
sqlite3_value_numeric_type   jpayne@69: ** →  Best numeric datatype of the value jpayne@69: **
sqlite3_value_nochange   jpayne@69: ** →  True if the column is unchanged in an UPDATE jpayne@69: ** against a virtual table. jpayne@69: **
sqlite3_value_frombind   jpayne@69: ** →  True if value originated from a [bound parameter] jpayne@69: **
jpayne@69: ** jpayne@69: ** Details: jpayne@69: ** jpayne@69: ** These routines extract type, size, and content information from jpayne@69: ** [protected sqlite3_value] objects. Protected sqlite3_value objects jpayne@69: ** are used to pass parameter information into the functions that jpayne@69: ** implement [application-defined SQL functions] and [virtual tables]. jpayne@69: ** jpayne@69: ** These routines work only with [protected sqlite3_value] objects. jpayne@69: ** Any attempt to use these routines on an [unprotected sqlite3_value] jpayne@69: ** is not threadsafe. jpayne@69: ** jpayne@69: ** ^These routines work just like the corresponding [column access functions] jpayne@69: ** except that these routines take a single [protected sqlite3_value] object jpayne@69: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. jpayne@69: ** jpayne@69: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string jpayne@69: ** in the native byte-order of the host machine. ^The jpayne@69: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces jpayne@69: ** extract UTF-16 strings as big-endian and little-endian respectively. jpayne@69: ** jpayne@69: ** ^If [sqlite3_value] object V was initialized jpayne@69: ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] jpayne@69: ** and if X and Y are strings that compare equal according to strcmp(X,Y), jpayne@69: ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, jpayne@69: ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() jpayne@69: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. jpayne@69: ** jpayne@69: ** ^(The sqlite3_value_type(V) interface returns the jpayne@69: ** [SQLITE_INTEGER | datatype code] for the initial datatype of the jpayne@69: ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], jpayne@69: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ jpayne@69: ** Other interfaces might change the datatype for an sqlite3_value object. jpayne@69: ** For example, if the datatype is initially SQLITE_INTEGER and jpayne@69: ** sqlite3_value_text(V) is called to extract a text value for that jpayne@69: ** integer, then subsequent calls to sqlite3_value_type(V) might return jpayne@69: ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion jpayne@69: ** occurs is undefined and may change from one release of SQLite to the next. jpayne@69: ** jpayne@69: ** ^(The sqlite3_value_numeric_type() interface attempts to apply jpayne@69: ** numeric affinity to the value. This means that an attempt is jpayne@69: ** made to convert the value to an integer or floating point. If jpayne@69: ** such a conversion is possible without loss of information (in other jpayne@69: ** words, if the value is a string that looks like a number) jpayne@69: ** then the conversion is performed. Otherwise no conversion occurs. jpayne@69: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ jpayne@69: ** jpayne@69: ** ^Within the [xUpdate] method of a [virtual table], the jpayne@69: ** sqlite3_value_nochange(X) interface returns true if and only if jpayne@69: ** the column corresponding to X is unchanged by the UPDATE operation jpayne@69: ** that the xUpdate method call was invoked to implement and if jpayne@69: ** and the prior [xColumn] method call that was invoked to extracted jpayne@69: ** the value for that column returned without setting a result (probably jpayne@69: ** because it queried [sqlite3_vtab_nochange()] and found that the column jpayne@69: ** was unchanging). ^Within an [xUpdate] method, any value for which jpayne@69: ** sqlite3_value_nochange(X) is true will in all other respects appear jpayne@69: ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other jpayne@69: ** than within an [xUpdate] method call for an UPDATE statement, then jpayne@69: ** the return value is arbitrary and meaningless. jpayne@69: ** jpayne@69: ** ^The sqlite3_value_frombind(X) interface returns non-zero if the jpayne@69: ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] jpayne@69: ** interfaces. ^If X comes from an SQL literal value, or a table column, jpayne@69: ** or an expression, then sqlite3_value_frombind(X) returns zero. jpayne@69: ** jpayne@69: ** Please pay particular attention to the fact that the pointer returned jpayne@69: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or jpayne@69: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to jpayne@69: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], jpayne@69: ** or [sqlite3_value_text16()]. jpayne@69: ** jpayne@69: ** These routines must be called from the same thread as jpayne@69: ** the SQL function that supplied the [sqlite3_value*] parameters. jpayne@69: ** jpayne@69: ** As long as the input parameter is correct, these routines can only jpayne@69: ** fail if an out-of-memory error occurs during a format conversion. jpayne@69: ** Only the following subset of interfaces are subject to out-of-memory jpayne@69: ** errors: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** If an out-of-memory error occurs, then the return value from these jpayne@69: ** routines is the same as if the column had contained an SQL NULL value. jpayne@69: ** Valid SQL NULL returns can be distinguished from out-of-memory errors jpayne@69: ** by invoking the [sqlite3_errcode()] immediately after the suspect jpayne@69: ** return value is obtained and before any jpayne@69: ** other SQLite interface is called on the same [database connection]. jpayne@69: */ jpayne@69: SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); jpayne@69: SQLITE_API double sqlite3_value_double(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_int(sqlite3_value*); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); jpayne@69: SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); jpayne@69: SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); jpayne@69: SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); jpayne@69: SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); jpayne@69: SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_bytes(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_type(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_nochange(sqlite3_value*); jpayne@69: SQLITE_API int sqlite3_value_frombind(sqlite3_value*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Report the internal text encoding state of an sqlite3_value object jpayne@69: ** METHOD: sqlite3_value jpayne@69: ** jpayne@69: ** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8], jpayne@69: ** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding jpayne@69: ** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X) jpayne@69: ** returns something other than SQLITE_TEXT, then the return value from jpayne@69: ** sqlite3_value_encoding(X) is meaningless. ^Calls to jpayne@69: ** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)], jpayne@69: ** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or jpayne@69: ** [sqlite3_value_bytes16(X)] might change the encoding of the value X and jpayne@69: ** thus change the return from subsequent calls to sqlite3_value_encoding(X). jpayne@69: ** jpayne@69: ** This routine is intended for used by applications that test and validate jpayne@69: ** the SQLite implementation. This routine is inquiring about the opaque jpayne@69: ** internal state of an [sqlite3_value] object. Ordinary applications should jpayne@69: ** not need to know what the internal state of an sqlite3_value object is and jpayne@69: ** hence should not need to use this interface. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_value_encoding(sqlite3_value*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Finding The Subtype Of SQL Values jpayne@69: ** METHOD: sqlite3_value jpayne@69: ** jpayne@69: ** The sqlite3_value_subtype(V) function returns the subtype for jpayne@69: ** an [application-defined SQL function] argument V. The subtype jpayne@69: ** information can be used to pass a limited amount of context from jpayne@69: ** one SQL function to another. Use the [sqlite3_result_subtype()] jpayne@69: ** routine to set the subtype for the return value of an SQL function. jpayne@69: ** jpayne@69: ** Every [application-defined SQL function] that invoke this interface jpayne@69: ** should include the [SQLITE_SUBTYPE] property in the text jpayne@69: ** encoding argument when the function is [sqlite3_create_function|registered]. jpayne@69: ** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype() jpayne@69: ** might return zero instead of the upstream subtype in some corner cases. jpayne@69: */ jpayne@69: SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Copy And Free SQL Values jpayne@69: ** METHOD: sqlite3_value jpayne@69: ** jpayne@69: ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] jpayne@69: ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned jpayne@69: ** is a [protected sqlite3_value] object even if the input is not. jpayne@69: ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a jpayne@69: ** memory allocation fails. ^If V is a [pointer value], then the result jpayne@69: ** of sqlite3_value_dup(V) is a NULL value. jpayne@69: ** jpayne@69: ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object jpayne@69: ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer jpayne@69: ** then sqlite3_value_free(V) is a harmless no-op. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); jpayne@69: SQLITE_API void sqlite3_value_free(sqlite3_value*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain Aggregate Function Context jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** Implementations of aggregate SQL functions use this jpayne@69: ** routine to allocate memory for storing their state. jpayne@69: ** jpayne@69: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called jpayne@69: ** for a particular aggregate function, SQLite allocates jpayne@69: ** N bytes of memory, zeroes out that memory, and returns a pointer jpayne@69: ** to the new memory. ^On second and subsequent calls to jpayne@69: ** sqlite3_aggregate_context() for the same aggregate function instance, jpayne@69: ** the same buffer is returned. Sqlite3_aggregate_context() is normally jpayne@69: ** called once for each invocation of the xStep callback and then one jpayne@69: ** last time when the xFinal callback is invoked. ^(When no rows match jpayne@69: ** an aggregate query, the xStep() callback of the aggregate function jpayne@69: ** implementation is never called and xFinal() is called exactly once. jpayne@69: ** In those cases, sqlite3_aggregate_context() might be called for the jpayne@69: ** first time from within xFinal().)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer jpayne@69: ** when first called if N is less than or equal to zero or if a memory jpayne@69: ** allocation error occurs. jpayne@69: ** jpayne@69: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is jpayne@69: ** determined by the N parameter on first successful call. Changing the jpayne@69: ** value of N in any subsequent call to sqlite3_aggregate_context() within jpayne@69: ** the same aggregate function instance will not resize the memory jpayne@69: ** allocation.)^ Within the xFinal callback, it is customary to set jpayne@69: ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no jpayne@69: ** pointless memory allocations occur. jpayne@69: ** jpayne@69: ** ^SQLite automatically frees the memory allocated by jpayne@69: ** sqlite3_aggregate_context() when the aggregate query concludes. jpayne@69: ** jpayne@69: ** The first parameter must be a copy of the jpayne@69: ** [sqlite3_context | SQL function context] that is the first parameter jpayne@69: ** to the xStep or xFinal callback routine that implements the aggregate jpayne@69: ** function. jpayne@69: ** jpayne@69: ** This routine must be called from the same thread in which jpayne@69: ** the aggregate SQL function is running. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: User Data For Functions jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** ^The sqlite3_user_data() interface returns a copy of jpayne@69: ** the pointer that was the pUserData parameter (the 5th parameter) jpayne@69: ** of the [sqlite3_create_function()] jpayne@69: ** and [sqlite3_create_function16()] routines that originally jpayne@69: ** registered the application defined function. jpayne@69: ** jpayne@69: ** This routine must be called from the same thread in which jpayne@69: ** the application-defined function is running. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_user_data(sqlite3_context*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Connection For Functions jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** ^The sqlite3_context_db_handle() interface returns a copy of jpayne@69: ** the pointer to the [database connection] (the 1st parameter) jpayne@69: ** of the [sqlite3_create_function()] jpayne@69: ** and [sqlite3_create_function16()] routines that originally jpayne@69: ** registered the application defined function. jpayne@69: */ jpayne@69: SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Function Auxiliary Data jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** These functions may be used by (non-aggregate) SQL functions to jpayne@69: ** associate auxiliary data with argument values. If the same argument jpayne@69: ** value is passed to multiple invocations of the same SQL function during jpayne@69: ** query execution, under some circumstances the associated auxiliary data jpayne@69: ** might be preserved. An example of where this might be useful is in a jpayne@69: ** regular-expression matching function. The compiled version of the regular jpayne@69: ** expression can be stored as auxiliary data associated with the pattern string. jpayne@69: ** Then as long as the pattern string remains the same, jpayne@69: ** the compiled regular expression can be reused on multiple jpayne@69: ** invocations of the same function. jpayne@69: ** jpayne@69: ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary data jpayne@69: ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument jpayne@69: ** value to the application-defined function. ^N is zero for the left-most jpayne@69: ** function argument. ^If there is no auxiliary data jpayne@69: ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface jpayne@69: ** returns a NULL pointer. jpayne@69: ** jpayne@69: ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the jpayne@69: ** N-th argument of the application-defined function. ^Subsequent jpayne@69: ** calls to sqlite3_get_auxdata(C,N) return P from the most recent jpayne@69: ** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or jpayne@69: ** NULL if the auxiliary data has been discarded. jpayne@69: ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, jpayne@69: ** SQLite will invoke the destructor function X with parameter P exactly jpayne@69: ** once, when the auxiliary data is discarded. jpayne@69: ** SQLite is free to discard the auxiliary data at any time, including: jpayne@69: ** jpayne@69: ** Note the last two bullets in particular. The destructor X in jpayne@69: ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the jpayne@69: ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() jpayne@69: ** should be called near the end of the function implementation and the jpayne@69: ** function implementation should not make any use of P after jpayne@69: ** sqlite3_set_auxdata() has been called. Furthermore, a call to jpayne@69: ** sqlite3_get_auxdata() that occurs immediately after a corresponding call jpayne@69: ** to sqlite3_set_auxdata() might still return NULL if an out-of-memory jpayne@69: ** condition occurred during the sqlite3_set_auxdata() call or if the jpayne@69: ** function is being evaluated during query planning rather than during jpayne@69: ** query execution. jpayne@69: ** jpayne@69: ** ^(In practice, auxiliary data is preserved between function calls for jpayne@69: ** function parameters that are compile-time constants, including literal jpayne@69: ** values and [parameters] and expressions composed from the same.)^ jpayne@69: ** jpayne@69: ** The value of the N parameter to these interfaces should be non-negative. jpayne@69: ** Future enhancements may make use of negative N values to define new jpayne@69: ** kinds of function caching behavior. jpayne@69: ** jpayne@69: ** These routines must be called from the same thread in which jpayne@69: ** the SQL function is running. jpayne@69: ** jpayne@69: ** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()]. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); jpayne@69: SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Connection Client Data jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** These functions are used to associate one or more named pointers jpayne@69: ** with a [database connection]. jpayne@69: ** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P jpayne@69: ** to be attached to [database connection] D using name N. Subsequent jpayne@69: ** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P jpayne@69: ** or a NULL pointer if there were no prior calls to jpayne@69: ** sqlite3_set_clientdata() with the same values of D and N. jpayne@69: ** Names are compared using strcmp() and are thus case sensitive. jpayne@69: ** jpayne@69: ** If P and X are both non-NULL, then the destructor X is invoked with jpayne@69: ** argument P on the first of the following occurrences: jpayne@69: ** jpayne@69: ** jpayne@69: ** SQLite does not do anything with client data other than invoke jpayne@69: ** destructors on the client data at the appropriate time. The intended jpayne@69: ** use for client data is to provide a mechanism for wrapper libraries jpayne@69: ** to store additional information about an SQLite database connection. jpayne@69: ** jpayne@69: ** There is no limit (other than available memory) on the number of different jpayne@69: ** client data pointers (with different names) that can be attached to a jpayne@69: ** single database connection. However, the implementation is optimized jpayne@69: ** for the case of having only one or two different client data names. jpayne@69: ** Applications and wrapper libraries are discouraged from using more than jpayne@69: ** one client data name each. jpayne@69: ** jpayne@69: ** There is no way to enumerate the client data pointers jpayne@69: ** associated with a database connection. The N parameter can be thought jpayne@69: ** of as a secret key such that only code that knows the secret key is able jpayne@69: ** to access the associated data. jpayne@69: ** jpayne@69: ** Security Warning: These interfaces should not be exposed in scripting jpayne@69: ** languages or in other circumstances where it might be possible for an jpayne@69: ** an attacker to invoke them. Any agent that can invoke these interfaces jpayne@69: ** can probably also take control of the process. jpayne@69: ** jpayne@69: ** Database connection client data is only available for SQLite jpayne@69: ** version 3.44.0 ([dateof:3.44.0]) and later. jpayne@69: ** jpayne@69: ** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()]. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*); jpayne@69: SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*)); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Constants Defining Special Destructor Behavior jpayne@69: ** jpayne@69: ** These are special values for the destructor that is passed in as the jpayne@69: ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor jpayne@69: ** argument is SQLITE_STATIC, it means that the content pointer is constant jpayne@69: ** and will never change. It does not need to be destroyed. ^The jpayne@69: ** SQLITE_TRANSIENT value means that the content will likely change in jpayne@69: ** the near future and that SQLite should make its own private copy of jpayne@69: ** the content before returning. jpayne@69: ** jpayne@69: ** The typedef is necessary to work around problems in certain jpayne@69: ** C++ compilers. jpayne@69: */ jpayne@69: typedef void (*sqlite3_destructor_type)(void*); jpayne@69: #define SQLITE_STATIC ((sqlite3_destructor_type)0) jpayne@69: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Setting The Result Of An SQL Function jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** These routines are used by the xFunc or xFinal callbacks that jpayne@69: ** implement SQL functions and aggregates. See jpayne@69: ** [sqlite3_create_function()] and [sqlite3_create_function16()] jpayne@69: ** for additional information. jpayne@69: ** jpayne@69: ** These functions work very much like the [parameter binding] family of jpayne@69: ** functions used to bind values to host parameters in prepared statements. jpayne@69: ** Refer to the [SQL parameter] documentation for additional information. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_blob() interface sets the result from jpayne@69: ** an application-defined function to be the BLOB whose content is pointed jpayne@69: ** to by the second parameter and which is N bytes long where N is the jpayne@69: ** third parameter. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) jpayne@69: ** interfaces set the result of the application-defined function to be jpayne@69: ** a BLOB containing all zero bytes and N bytes in size. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_double() interface sets the result from jpayne@69: ** an application-defined function to be a floating point value specified jpayne@69: ** by its 2nd argument. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions jpayne@69: ** cause the implemented SQL function to throw an exception. jpayne@69: ** ^SQLite uses the string pointed to by the jpayne@69: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() jpayne@69: ** as the text of an error message. ^SQLite interprets the error jpayne@69: ** message string from sqlite3_result_error() as UTF-8. ^SQLite jpayne@69: ** interprets the string from sqlite3_result_error16() as UTF-16 using jpayne@69: ** the same [byte-order determination rules] as [sqlite3_bind_text16()]. jpayne@69: ** ^If the third parameter to sqlite3_result_error() jpayne@69: ** or sqlite3_result_error16() is negative then SQLite takes as the error jpayne@69: ** message all text up through the first zero character. jpayne@69: ** ^If the third parameter to sqlite3_result_error() or jpayne@69: ** sqlite3_result_error16() is non-negative then SQLite takes that many jpayne@69: ** bytes (not characters) from the 2nd parameter as the error message. jpayne@69: ** ^The sqlite3_result_error() and sqlite3_result_error16() jpayne@69: ** routines make a private copy of the error message text before jpayne@69: ** they return. Hence, the calling function can deallocate or jpayne@69: ** modify the text after they return without harm. jpayne@69: ** ^The sqlite3_result_error_code() function changes the error code jpayne@69: ** returned by SQLite as a result of an error in a function. ^By default, jpayne@69: ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() jpayne@69: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an jpayne@69: ** error indicating that a string or BLOB is too long to represent. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an jpayne@69: ** error indicating that a memory allocation failed. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_int() interface sets the return value jpayne@69: ** of the application-defined function to be the 32-bit signed integer jpayne@69: ** value given in the 2nd argument. jpayne@69: ** ^The sqlite3_result_int64() interface sets the return value jpayne@69: ** of the application-defined function to be the 64-bit signed integer jpayne@69: ** value given in the 2nd argument. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_null() interface sets the return value jpayne@69: ** of the application-defined function to be NULL. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_text(), sqlite3_result_text16(), jpayne@69: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces jpayne@69: ** set the return value of the application-defined function to be jpayne@69: ** a text string which is represented as UTF-8, UTF-16 native byte order, jpayne@69: ** UTF-16 little endian, or UTF-16 big endian, respectively. jpayne@69: ** ^The sqlite3_result_text64() interface sets the return value of an jpayne@69: ** application-defined function to be a text string in an encoding jpayne@69: ** specified by the fifth (and last) parameter, which must be one jpayne@69: ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. jpayne@69: ** ^SQLite takes the text result from the application from jpayne@69: ** the 2nd parameter of the sqlite3_result_text* interfaces. jpayne@69: ** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces jpayne@69: ** other than sqlite3_result_text64() is negative, then SQLite computes jpayne@69: ** the string length itself by searching the 2nd parameter for the first jpayne@69: ** zero character. jpayne@69: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces jpayne@69: ** is non-negative, then as many bytes (not characters) of the text jpayne@69: ** pointed to by the 2nd parameter are taken as the application-defined jpayne@69: ** function result. If the 3rd parameter is non-negative, then it jpayne@69: ** must be the byte offset into the string where the NUL terminator would jpayne@69: ** appear if the string where NUL terminated. If any NUL characters occur jpayne@69: ** in the string at a byte offset that is less than the value of the 3rd jpayne@69: ** parameter, then the resulting string will contain embedded NULs and the jpayne@69: ** result of expressions operating on strings with embedded NULs is undefined. jpayne@69: ** ^If the 4th parameter to the sqlite3_result_text* interfaces jpayne@69: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that jpayne@69: ** function as the destructor on the text or BLOB result when it has jpayne@69: ** finished using that result. jpayne@69: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to jpayne@69: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite jpayne@69: ** assumes that the text or BLOB result is in constant space and does not jpayne@69: ** copy the content of the parameter nor call a destructor on the content jpayne@69: ** when it has finished using that result. jpayne@69: ** ^If the 4th parameter to the sqlite3_result_text* interfaces jpayne@69: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT jpayne@69: ** then SQLite makes a copy of the result into space obtained jpayne@69: ** from [sqlite3_malloc()] before it returns. jpayne@69: ** jpayne@69: ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and jpayne@69: ** sqlite3_result_text16be() routines, and for sqlite3_result_text64() jpayne@69: ** when the encoding is not UTF8, if the input UTF16 begins with a jpayne@69: ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the jpayne@69: ** string and the rest of the string is interpreted according to the jpayne@69: ** byte-order specified by the BOM. ^The byte-order specified by jpayne@69: ** the BOM at the beginning of the text overrides the byte-order jpayne@69: ** specified by the interface procedure. ^So, for example, if jpayne@69: ** sqlite3_result_text16le() is invoked with text that begins jpayne@69: ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the jpayne@69: ** first two bytes of input are skipped and the remaining input jpayne@69: ** is interpreted as UTF16BE text. jpayne@69: ** jpayne@69: ** ^For UTF16 input text to the sqlite3_result_text16(), jpayne@69: ** sqlite3_result_text16be(), sqlite3_result_text16le(), and jpayne@69: ** sqlite3_result_text64() routines, if the text contains invalid jpayne@69: ** UTF16 characters, the invalid characters might be converted jpayne@69: ** into the unicode replacement character, U+FFFD. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_value() interface sets the result of jpayne@69: ** the application-defined function to be a copy of the jpayne@69: ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The jpayne@69: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] jpayne@69: ** so that the [sqlite3_value] specified in the parameter may change or jpayne@69: ** be deallocated after sqlite3_result_value() returns without harm. jpayne@69: ** ^A [protected sqlite3_value] object may always be used where an jpayne@69: ** [unprotected sqlite3_value] object is required, so either jpayne@69: ** kind of [sqlite3_value] object can be used with this interface. jpayne@69: ** jpayne@69: ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an jpayne@69: ** SQL NULL value, just like [sqlite3_result_null(C)], except that it jpayne@69: ** also associates the host-language pointer P or type T with that jpayne@69: ** NULL value such that the pointer can be retrieved within an jpayne@69: ** [application-defined SQL function] using [sqlite3_value_pointer()]. jpayne@69: ** ^If the D parameter is not NULL, then it is a pointer to a destructor jpayne@69: ** for the P parameter. ^SQLite invokes D with P as its only argument jpayne@69: ** when SQLite is finished with P. The T parameter should be a static jpayne@69: ** string and preferably a string literal. The sqlite3_result_pointer() jpayne@69: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. jpayne@69: ** jpayne@69: ** If these routines are called from within the different thread jpayne@69: ** than the one containing the application-defined function that received jpayne@69: ** the [sqlite3_context] pointer, the results are undefined. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, jpayne@69: sqlite3_uint64,void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_double(sqlite3_context*, double); jpayne@69: SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); jpayne@69: SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); jpayne@69: SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); jpayne@69: SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); jpayne@69: SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); jpayne@69: SQLITE_API void sqlite3_result_int(sqlite3_context*, int); jpayne@69: SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); jpayne@69: SQLITE_API void sqlite3_result_null(sqlite3_context*); jpayne@69: SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, jpayne@69: void(*)(void*), unsigned char encoding); jpayne@69: SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); jpayne@69: SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); jpayne@69: SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); jpayne@69: SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Setting The Subtype Of An SQL Function jpayne@69: ** METHOD: sqlite3_context jpayne@69: ** jpayne@69: ** The sqlite3_result_subtype(C,T) function causes the subtype of jpayne@69: ** the result from the [application-defined SQL function] with jpayne@69: ** [sqlite3_context] C to be the value T. Only the lower 8 bits jpayne@69: ** of the subtype T are preserved in current versions of SQLite; jpayne@69: ** higher order bits are discarded. jpayne@69: ** The number of subtype bytes preserved by SQLite might increase jpayne@69: ** in future releases of SQLite. jpayne@69: ** jpayne@69: ** Every [application-defined SQL function] that invokes this interface jpayne@69: ** should include the [SQLITE_RESULT_SUBTYPE] property in its jpayne@69: ** text encoding argument when the SQL function is jpayne@69: ** [sqlite3_create_function|registered]. If the [SQLITE_RESULT_SUBTYPE] jpayne@69: ** property is omitted from the function that invokes sqlite3_result_subtype(), jpayne@69: ** then in some cases the sqlite3_result_subtype() might fail to set jpayne@69: ** the result subtype. jpayne@69: ** jpayne@69: ** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any jpayne@69: ** SQL function that invokes the sqlite3_result_subtype() interface jpayne@69: ** and that does not have the SQLITE_RESULT_SUBTYPE property will raise jpayne@69: ** an error. Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1 jpayne@69: ** by default. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Define New Collating Sequences jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These functions add, remove, or modify a [collation] associated jpayne@69: ** with the [database connection] specified as the first argument. jpayne@69: ** jpayne@69: ** ^The name of the collation is a UTF-8 string jpayne@69: ** for sqlite3_create_collation() and sqlite3_create_collation_v2() jpayne@69: ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). jpayne@69: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are jpayne@69: ** considered to be the same name. jpayne@69: ** jpayne@69: ** ^(The third argument (eTextRep) must be one of the constants: jpayne@69: ** )^ jpayne@69: ** ^The eTextRep argument determines the encoding of strings passed jpayne@69: ** to the collating function callback, xCompare. jpayne@69: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep jpayne@69: ** force strings to be UTF16 with native byte order. jpayne@69: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin jpayne@69: ** on an even byte address. jpayne@69: ** jpayne@69: ** ^The fourth argument, pArg, is an application data pointer that is passed jpayne@69: ** through as the first argument to the collating function callback. jpayne@69: ** jpayne@69: ** ^The fifth argument, xCompare, is a pointer to the collating function. jpayne@69: ** ^Multiple collating functions can be registered using the same name but jpayne@69: ** with different eTextRep parameters and SQLite will use whichever jpayne@69: ** function requires the least amount of data transformation. jpayne@69: ** ^If the xCompare argument is NULL then the collating function is jpayne@69: ** deleted. ^When all collating functions having the same name are deleted, jpayne@69: ** that collation is no longer usable. jpayne@69: ** jpayne@69: ** ^The collating function callback is invoked with a copy of the pArg jpayne@69: ** application data pointer and with two strings in the encoding specified jpayne@69: ** by the eTextRep argument. The two integer parameters to the collating jpayne@69: ** function callback are the length of the two strings, in bytes. The collating jpayne@69: ** function must return an integer that is negative, zero, or positive jpayne@69: ** if the first string is less than, equal to, or greater than the second, jpayne@69: ** respectively. A collating function must always return the same answer jpayne@69: ** given the same inputs. If two or more collating functions are registered jpayne@69: ** to the same collation name (using different eTextRep values) then all jpayne@69: ** must give an equivalent answer when invoked with equivalent strings. jpayne@69: ** The collating function must obey the following properties for all jpayne@69: ** strings A, B, and C: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  1. If A==B then B==A. jpayne@69: **
  2. If A==B and B==C then A==C. jpayne@69: **
  3. If A<B THEN B>A. jpayne@69: **
  4. If A<B and B<C then A<C. jpayne@69: **
jpayne@69: ** jpayne@69: ** If a collating function fails any of the above constraints and that jpayne@69: ** collating function is registered and used, then the behavior of SQLite jpayne@69: ** is undefined. jpayne@69: ** jpayne@69: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() jpayne@69: ** with the addition that the xDestroy callback is invoked on pArg when jpayne@69: ** the collating function is deleted. jpayne@69: ** ^Collating functions are deleted when they are overridden by later jpayne@69: ** calls to the collation creation functions or when the jpayne@69: ** [database connection] is closed using [sqlite3_close()]. jpayne@69: ** jpayne@69: ** ^The xDestroy callback is not called if the jpayne@69: ** sqlite3_create_collation_v2() function fails. Applications that invoke jpayne@69: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should jpayne@69: ** check the return code and dispose of the application data pointer jpayne@69: ** themselves rather than expecting SQLite to deal with it for them. jpayne@69: ** This is different from every other SQLite interface. The inconsistency jpayne@69: ** is unfortunate but cannot be changed without breaking backwards jpayne@69: ** compatibility. jpayne@69: ** jpayne@69: ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_create_collation( jpayne@69: sqlite3*, jpayne@69: const char *zName, jpayne@69: int eTextRep, jpayne@69: void *pArg, jpayne@69: int(*xCompare)(void*,int,const void*,int,const void*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_collation_v2( jpayne@69: sqlite3*, jpayne@69: const char *zName, jpayne@69: int eTextRep, jpayne@69: void *pArg, jpayne@69: int(*xCompare)(void*,int,const void*,int,const void*), jpayne@69: void(*xDestroy)(void*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_collation16( jpayne@69: sqlite3*, jpayne@69: const void *zName, jpayne@69: int eTextRep, jpayne@69: void *pArg, jpayne@69: int(*xCompare)(void*,int,const void*,int,const void*) jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Collation Needed Callbacks jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^To avoid having to register all collation sequences before a database jpayne@69: ** can be used, a single callback function may be registered with the jpayne@69: ** [database connection] to be invoked whenever an undefined collation jpayne@69: ** sequence is required. jpayne@69: ** jpayne@69: ** ^If the function is registered using the sqlite3_collation_needed() API, jpayne@69: ** then it is passed the names of undefined collation sequences as strings jpayne@69: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, jpayne@69: ** the names are passed as UTF-16 in machine native byte order. jpayne@69: ** ^A call to either function replaces the existing collation-needed callback. jpayne@69: ** jpayne@69: ** ^(When the callback is invoked, the first argument passed is a copy jpayne@69: ** of the second argument to sqlite3_collation_needed() or jpayne@69: ** sqlite3_collation_needed16(). The second argument is the database jpayne@69: ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], jpayne@69: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation jpayne@69: ** sequence function required. The fourth parameter is the name of the jpayne@69: ** required collation sequence.)^ jpayne@69: ** jpayne@69: ** The callback function should register the desired collation using jpayne@69: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or jpayne@69: ** [sqlite3_create_collation_v2()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_collation_needed( jpayne@69: sqlite3*, jpayne@69: void*, jpayne@69: void(*)(void*,sqlite3*,int eTextRep,const char*) jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_collation_needed16( jpayne@69: sqlite3*, jpayne@69: void*, jpayne@69: void(*)(void*,sqlite3*,int eTextRep,const void*) jpayne@69: ); jpayne@69: jpayne@69: #ifdef SQLITE_ENABLE_CEROD jpayne@69: /* jpayne@69: ** Specify the activation key for a CEROD database. Unless jpayne@69: ** activated, none of the CEROD routines will work. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_activate_cerod( jpayne@69: const char *zPassPhrase /* Activation phrase */ jpayne@69: ); jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Suspend Execution For A Short Time jpayne@69: ** jpayne@69: ** The sqlite3_sleep() function causes the current thread to suspend execution jpayne@69: ** for at least a number of milliseconds specified in its parameter. jpayne@69: ** jpayne@69: ** If the operating system does not support sleep requests with jpayne@69: ** millisecond time resolution, then the time will be rounded up to jpayne@69: ** the nearest second. The number of milliseconds of sleep actually jpayne@69: ** requested from the operating system is returned. jpayne@69: ** jpayne@69: ** ^SQLite implements this interface by calling the xSleep() jpayne@69: ** method of the default [sqlite3_vfs] object. If the xSleep() method jpayne@69: ** of the default VFS is not implemented correctly, or not implemented at jpayne@69: ** all, then the behavior of sqlite3_sleep() may deviate from the description jpayne@69: ** in the previous paragraphs. jpayne@69: ** jpayne@69: ** If a negative argument is passed to sqlite3_sleep() the results vary by jpayne@69: ** VFS and operating system. Some system treat a negative argument as an jpayne@69: ** instruction to sleep forever. Others understand it to mean do not sleep jpayne@69: ** at all. ^In SQLite version 3.42.0 and later, a negative jpayne@69: ** argument passed into sqlite3_sleep() is changed to zero before it is relayed jpayne@69: ** down into the xSleep method of the VFS. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_sleep(int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Name Of The Folder Holding Temporary Files jpayne@69: ** jpayne@69: ** ^(If this global variable is made to point to a string which is jpayne@69: ** the name of a folder (a.k.a. directory), then all temporary files jpayne@69: ** created by SQLite when using a built-in [sqlite3_vfs | VFS] jpayne@69: ** will be placed in that directory.)^ ^If this variable jpayne@69: ** is a NULL pointer, then SQLite performs a search for an appropriate jpayne@69: ** temporary file directory. jpayne@69: ** jpayne@69: ** Applications are strongly discouraged from using this global variable. jpayne@69: ** It is required to set a temporary folder on Windows Runtime (WinRT). jpayne@69: ** But for all other platforms, it is highly recommended that applications jpayne@69: ** neither read nor write this variable. This global variable is a relic jpayne@69: ** that exists for backwards compatibility of legacy applications and should jpayne@69: ** be avoided in new projects. jpayne@69: ** jpayne@69: ** It is not safe to read or modify this variable in more than one jpayne@69: ** thread at a time. It is not safe to read or modify this variable jpayne@69: ** if a [database connection] is being used at the same time in a separate jpayne@69: ** thread. jpayne@69: ** It is intended that this variable be set once jpayne@69: ** as part of process initialization and before any SQLite interface jpayne@69: ** routines have been called and that this variable remain unchanged jpayne@69: ** thereafter. jpayne@69: ** jpayne@69: ** ^The [temp_store_directory pragma] may modify this variable and cause jpayne@69: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, jpayne@69: ** the [temp_store_directory pragma] always assumes that any string jpayne@69: ** that this variable points to is held in memory obtained from jpayne@69: ** [sqlite3_malloc] and the pragma may attempt to free that memory jpayne@69: ** using [sqlite3_free]. jpayne@69: ** Hence, if this variable is modified directly, either it should be jpayne@69: ** made NULL or made to point to memory obtained from [sqlite3_malloc] jpayne@69: ** or else the use of the [temp_store_directory pragma] should be avoided. jpayne@69: ** Except when requested by the [temp_store_directory pragma], SQLite jpayne@69: ** does not free the memory that sqlite3_temp_directory points to. If jpayne@69: ** the application wants that memory to be freed, it must do jpayne@69: ** so itself, taking care to only do so after all [database connection] jpayne@69: ** objects have been destroyed. jpayne@69: ** jpayne@69: ** Note to Windows Runtime users: The temporary directory must be set jpayne@69: ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various jpayne@69: ** features that require the use of temporary files may fail. Here is an jpayne@69: ** example of how to do this using C++ with the Windows Runtime: jpayne@69: ** jpayne@69: ** 
jpayne@69: ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
jpayne@69: **       TemporaryFolder->Path->Data();
jpayne@69: ** char zPathBuf[MAX_PATH + 1];
jpayne@69: ** memset(zPathBuf, 0, sizeof(zPathBuf));
jpayne@69: ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
jpayne@69: **       NULL, NULL);
jpayne@69: ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
jpayne@69: **
jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Name Of The Folder Holding Database Files jpayne@69: ** jpayne@69: ** ^(If this global variable is made to point to a string which is jpayne@69: ** the name of a folder (a.k.a. directory), then all database files jpayne@69: ** specified with a relative pathname and created or accessed by jpayne@69: ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed jpayne@69: ** to be relative to that directory.)^ ^If this variable is a NULL jpayne@69: ** pointer, then SQLite assumes that all database files specified jpayne@69: ** with a relative pathname are relative to the current directory jpayne@69: ** for the process. Only the windows VFS makes use of this global jpayne@69: ** variable; it is ignored by the unix VFS. jpayne@69: ** jpayne@69: ** Changing the value of this variable while a database connection is jpayne@69: ** open can result in a corrupt database. jpayne@69: ** jpayne@69: ** It is not safe to read or modify this variable in more than one jpayne@69: ** thread at a time. It is not safe to read or modify this variable jpayne@69: ** if a [database connection] is being used at the same time in a separate jpayne@69: ** thread. jpayne@69: ** It is intended that this variable be set once jpayne@69: ** as part of process initialization and before any SQLite interface jpayne@69: ** routines have been called and that this variable remain unchanged jpayne@69: ** thereafter. jpayne@69: ** jpayne@69: ** ^The [data_store_directory pragma] may modify this variable and cause jpayne@69: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, jpayne@69: ** the [data_store_directory pragma] always assumes that any string jpayne@69: ** that this variable points to is held in memory obtained from jpayne@69: ** [sqlite3_malloc] and the pragma may attempt to free that memory jpayne@69: ** using [sqlite3_free]. jpayne@69: ** Hence, if this variable is modified directly, either it should be jpayne@69: ** made NULL or made to point to memory obtained from [sqlite3_malloc] jpayne@69: ** or else the use of the [data_store_directory pragma] should be avoided. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Win32 Specific Interface jpayne@69: ** jpayne@69: ** These interfaces are available only on Windows. The jpayne@69: ** [sqlite3_win32_set_directory] interface is used to set the value associated jpayne@69: ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to jpayne@69: ** zValue, depending on the value of the type parameter. The zValue parameter jpayne@69: ** should be NULL to cause the previous value to be freed via [sqlite3_free]; jpayne@69: ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] jpayne@69: ** prior to being used. The [sqlite3_win32_set_directory] interface returns jpayne@69: ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, jpayne@69: ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the jpayne@69: ** [sqlite3_data_directory] variable is intended to act as a replacement for jpayne@69: ** the current directory on the sub-platforms of Win32 where that concept is jpayne@69: ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and jpayne@69: ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the jpayne@69: ** sqlite3_win32_set_directory interface except the string parameter must be jpayne@69: ** UTF-8 or UTF-16, respectively. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_win32_set_directory( jpayne@69: unsigned long type, /* Identifier for directory being set or reset */ jpayne@69: void *zValue /* New value for directory being set or reset */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); jpayne@69: SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Win32 Directory Types jpayne@69: ** jpayne@69: ** These macros are only available on Windows. They define the allowed values jpayne@69: ** for the type argument to the [sqlite3_win32_set_directory] interface. jpayne@69: */ jpayne@69: #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 jpayne@69: #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Test For Auto-Commit Mode jpayne@69: ** KEYWORDS: {autocommit mode} jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_get_autocommit() interface returns non-zero or jpayne@69: ** zero if the given database connection is or is not in autocommit mode, jpayne@69: ** respectively. ^Autocommit mode is on by default. jpayne@69: ** ^Autocommit mode is disabled by a [BEGIN] statement. jpayne@69: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. jpayne@69: ** jpayne@69: ** If certain kinds of errors occur on a statement within a multi-statement jpayne@69: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], jpayne@69: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the jpayne@69: ** transaction might be rolled back automatically. The only way to jpayne@69: ** find out whether SQLite automatically rolled back the transaction after jpayne@69: ** an error is to use this function. jpayne@69: ** jpayne@69: ** If another thread changes the autocommit status of the database jpayne@69: ** connection while this routine is running, then the return value jpayne@69: ** is undefined. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_get_autocommit(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Find The Database Handle Of A Prepared Statement jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^The sqlite3_db_handle interface returns the [database connection] handle jpayne@69: ** to which a [prepared statement] belongs. ^The [database connection] jpayne@69: ** returned by sqlite3_db_handle is the same [database connection] jpayne@69: ** that was the first argument jpayne@69: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to jpayne@69: ** create the statement in the first place. jpayne@69: */ jpayne@69: SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Return The Schema Name For A Database Connection jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name jpayne@69: ** for the N-th database on database connection D, or a NULL pointer of N is jpayne@69: ** out of range. An N value of 0 means the main database file. An N of 1 is jpayne@69: ** the "temp" schema. Larger values of N correspond to various ATTACH-ed jpayne@69: ** databases. jpayne@69: ** jpayne@69: ** Space to hold the string that is returned by sqlite3_db_name() is managed jpayne@69: ** by SQLite itself. The string might be deallocated by any operation that jpayne@69: ** changes the schema, including [ATTACH] or [DETACH] or calls to jpayne@69: ** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that jpayne@69: ** occur on a different thread. Applications that need to jpayne@69: ** remember the string long-term should make their own copy. Applications that jpayne@69: ** are accessing the same database connection simultaneously on multiple jpayne@69: ** threads should mutex-protect calls to this API and should make their own jpayne@69: ** private copy of the result prior to releasing the mutex. jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Return The Filename For A Database Connection jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename jpayne@69: ** associated with database N of connection D. jpayne@69: ** ^If there is no attached database N on the database jpayne@69: ** connection D, or if database N is a temporary or in-memory database, then jpayne@69: ** this function will return either a NULL pointer or an empty string. jpayne@69: ** jpayne@69: ** ^The string value returned by this routine is owned and managed by jpayne@69: ** the database connection. ^The value will be valid until the database N jpayne@69: ** is [DETACH]-ed or until the database connection closes. jpayne@69: ** jpayne@69: ** ^The filename returned by this function is the output of the jpayne@69: ** xFullPathname method of the [VFS]. ^In other words, the filename jpayne@69: ** will be an absolute pathname, even if the filename used jpayne@69: ** to open the database originally was a URI or relative pathname. jpayne@69: ** jpayne@69: ** If the filename pointer returned by this routine is not NULL, then it jpayne@69: ** can be used as the filename input parameter to these routines: jpayne@69: ** jpayne@69: */ jpayne@69: SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine if a database is read-only jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N jpayne@69: ** of connection D is read-only, 0 if it is read/write, or -1 if N is not jpayne@69: ** the name of a database on connection D. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine the transaction state of a database jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_txn_state(D,S) interface returns the current jpayne@69: ** [transaction state] of schema S in database connection D. ^If S is NULL, jpayne@69: ** then the highest transaction state of any schema on database connection D jpayne@69: ** is returned. Transaction states are (in order of lowest to highest): jpayne@69: **
    jpayne@69: **
  1. SQLITE_TXN_NONE jpayne@69: **
  2. SQLITE_TXN_READ jpayne@69: **
  3. SQLITE_TXN_WRITE jpayne@69: **
jpayne@69: ** ^If the S argument to sqlite3_txn_state(D,S) is not the name of jpayne@69: ** a valid schema, then -1 is returned. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Allowed return values from sqlite3_txn_state() jpayne@69: ** KEYWORDS: {transaction state} jpayne@69: ** jpayne@69: ** These constants define the current transaction state of a database file. jpayne@69: ** ^The [sqlite3_txn_state(D,S)] interface returns one of these jpayne@69: ** constants in order to describe the transaction state of schema S jpayne@69: ** in [database connection] D. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_TXN_NONE]]
SQLITE_TXN_NONE
jpayne@69: **
The SQLITE_TXN_NONE state means that no transaction is currently jpayne@69: ** pending.
jpayne@69: ** jpayne@69: ** [[SQLITE_TXN_READ]]
SQLITE_TXN_READ
jpayne@69: **
The SQLITE_TXN_READ state means that the database is currently jpayne@69: ** in a read transaction. Content has been read from the database file jpayne@69: ** but nothing in the database file has changed. The transaction state jpayne@69: ** will advanced to SQLITE_TXN_WRITE if any changes occur and there are jpayne@69: ** no other conflicting concurrent write transactions. The transaction jpayne@69: ** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or jpayne@69: ** [COMMIT].
jpayne@69: ** jpayne@69: ** [[SQLITE_TXN_WRITE]]
SQLITE_TXN_WRITE
jpayne@69: **
The SQLITE_TXN_WRITE state means that the database is currently jpayne@69: ** in a write transaction. Content has been written to the database file jpayne@69: ** but has not yet committed. The transaction state will change to jpayne@69: ** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].
jpayne@69: */ jpayne@69: #define SQLITE_TXN_NONE 0 jpayne@69: #define SQLITE_TXN_READ 1 jpayne@69: #define SQLITE_TXN_WRITE 2 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Find the next prepared statement jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This interface returns a pointer to the next [prepared statement] after jpayne@69: ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL jpayne@69: ** then this interface returns a pointer to the first prepared statement jpayne@69: ** associated with the database connection pDb. ^If no prepared statement jpayne@69: ** satisfies the conditions of this routine, it returns NULL. jpayne@69: ** jpayne@69: ** The [database connection] pointer D in a call to jpayne@69: ** [sqlite3_next_stmt(D,S)] must refer to an open database jpayne@69: ** connection and in particular must not be a NULL pointer. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Commit And Rollback Notification Callbacks jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_commit_hook() interface registers a callback jpayne@69: ** function to be invoked whenever a transaction is [COMMIT | committed]. jpayne@69: ** ^Any callback set by a previous call to sqlite3_commit_hook() jpayne@69: ** for the same database connection is overridden. jpayne@69: ** ^The sqlite3_rollback_hook() interface registers a callback jpayne@69: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. jpayne@69: ** ^Any callback set by a previous call to sqlite3_rollback_hook() jpayne@69: ** for the same database connection is overridden. jpayne@69: ** ^The pArg argument is passed through to the callback. jpayne@69: ** ^If the callback on a commit hook function returns non-zero, jpayne@69: ** then the commit is converted into a rollback. jpayne@69: ** jpayne@69: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions jpayne@69: ** return the P argument from the previous call of the same function jpayne@69: ** on the same [database connection] D, or NULL for jpayne@69: ** the first call for each function on D. jpayne@69: ** jpayne@69: ** The commit and rollback hook callbacks are not reentrant. jpayne@69: ** The callback implementation must not do anything that will modify jpayne@69: ** the database connection that invoked the callback. Any actions jpayne@69: ** to modify the database connection must be deferred until after the jpayne@69: ** completion of the [sqlite3_step()] call that triggered the commit jpayne@69: ** or rollback hook in the first place. jpayne@69: ** Note that running any other SQL statements, including SELECT statements, jpayne@69: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify jpayne@69: ** the database connections for the meaning of "modify" in this paragraph. jpayne@69: ** jpayne@69: ** ^Registering a NULL function disables the callback. jpayne@69: ** jpayne@69: ** ^When the commit hook callback routine returns zero, the [COMMIT] jpayne@69: ** operation is allowed to continue normally. ^If the commit hook jpayne@69: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. jpayne@69: ** ^The rollback hook is invoked on a rollback that results from a commit jpayne@69: ** hook returning non-zero, just as it would be with any other rollback. jpayne@69: ** jpayne@69: ** ^For the purposes of this API, a transaction is said to have been jpayne@69: ** rolled back if an explicit "ROLLBACK" statement is executed, or jpayne@69: ** an error or constraint causes an implicit rollback to occur. jpayne@69: ** ^The rollback callback is not invoked if a transaction is jpayne@69: ** automatically rolled back because the database connection is closed. jpayne@69: ** jpayne@69: ** See also the [sqlite3_update_hook()] interface. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); jpayne@69: SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Autovacuum Compaction Amount Callback jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback jpayne@69: ** function C that is invoked prior to each autovacuum of the database jpayne@69: ** file. ^The callback is passed a copy of the generic data pointer (P), jpayne@69: ** the schema-name of the attached database that is being autovacuumed, jpayne@69: ** the size of the database file in pages, the number of free pages, jpayne@69: ** and the number of bytes per page, respectively. The callback should jpayne@69: ** return the number of free pages that should be removed by the jpayne@69: ** autovacuum. ^If the callback returns zero, then no autovacuum happens. jpayne@69: ** ^If the value returned is greater than or equal to the number of jpayne@69: ** free pages, then a complete autovacuum happens. jpayne@69: ** jpayne@69: **

^If there are multiple ATTACH-ed database files that are being jpayne@69: ** modified as part of a transaction commit, then the autovacuum pages jpayne@69: ** callback is invoked separately for each file. jpayne@69: ** jpayne@69: **

The callback is not reentrant. The callback function should jpayne@69: ** not attempt to invoke any other SQLite interface. If it does, bad jpayne@69: ** things may happen, including segmentation faults and corrupt database jpayne@69: ** files. The callback function should be a simple function that jpayne@69: ** does some arithmetic on its input parameters and returns a result. jpayne@69: ** jpayne@69: ** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional jpayne@69: ** destructor for the P parameter. ^If X is not NULL, then X(P) is jpayne@69: ** invoked whenever the database connection closes or when the callback jpayne@69: ** is overwritten by another invocation of sqlite3_autovacuum_pages(). jpayne@69: ** jpayne@69: **

^There is only one autovacuum pages callback per database connection. jpayne@69: ** ^Each call to the sqlite3_autovacuum_pages() interface overrides all jpayne@69: ** previous invocations for that database connection. ^If the callback jpayne@69: ** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, jpayne@69: ** then the autovacuum steps callback is canceled. The return value jpayne@69: ** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might jpayne@69: ** be some other error code if something goes wrong. The current jpayne@69: ** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other jpayne@69: ** return codes might be added in future releases. jpayne@69: ** jpayne@69: **

If no autovacuum pages callback is specified (the usual case) or jpayne@69: ** a NULL pointer is provided for the callback, jpayne@69: ** then the default behavior is to vacuum all free pages. So, in other jpayne@69: ** words, the default behavior is the same as if the callback function jpayne@69: ** were something like this: jpayne@69: ** jpayne@69: ** 

jpayne@69: **     unsigned int demonstration_autovac_pages_callback(
jpayne@69: **       void *pClientData,
jpayne@69: **       const char *zSchema,
jpayne@69: **       unsigned int nDbPage,
jpayne@69: **       unsigned int nFreePage,
jpayne@69: **       unsigned int nBytePerPage
jpayne@69: **     ){
jpayne@69: **       return nFreePage;
jpayne@69: **     }
jpayne@69: **
jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_autovacuum_pages( jpayne@69: sqlite3 *db, jpayne@69: unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), jpayne@69: void*, jpayne@69: void(*)(void*) jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Data Change Notification Callbacks jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_update_hook() interface registers a callback function jpayne@69: ** with the [database connection] identified by the first argument jpayne@69: ** to be invoked whenever a row is updated, inserted or deleted in jpayne@69: ** a [rowid table]. jpayne@69: ** ^Any callback set by a previous call to this function jpayne@69: ** for the same database connection is overridden. jpayne@69: ** jpayne@69: ** ^The second argument is a pointer to the function to invoke when a jpayne@69: ** row is updated, inserted or deleted in a rowid table. jpayne@69: ** ^The first argument to the callback is a copy of the third argument jpayne@69: ** to sqlite3_update_hook(). jpayne@69: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], jpayne@69: ** or [SQLITE_UPDATE], depending on the operation that caused the callback jpayne@69: ** to be invoked. jpayne@69: ** ^The third and fourth arguments to the callback contain pointers to the jpayne@69: ** database and table name containing the affected row. jpayne@69: ** ^The final callback parameter is the [rowid] of the row. jpayne@69: ** ^In the case of an update, this is the [rowid] after the update takes place. jpayne@69: ** jpayne@69: ** ^(The update hook is not invoked when internal system tables are jpayne@69: ** modified (i.e. sqlite_sequence).)^ jpayne@69: ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. jpayne@69: ** jpayne@69: ** ^In the current implementation, the update hook jpayne@69: ** is not invoked when conflicting rows are deleted because of an jpayne@69: ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook jpayne@69: ** invoked when rows are deleted using the [truncate optimization]. jpayne@69: ** The exceptions defined in this paragraph might change in a future jpayne@69: ** release of SQLite. jpayne@69: ** jpayne@69: ** Whether the update hook is invoked before or after the jpayne@69: ** corresponding change is currently unspecified and may differ jpayne@69: ** depending on the type of change. Do not rely on the order of the jpayne@69: ** hook call with regards to the final result of the operation which jpayne@69: ** triggers the hook. jpayne@69: ** jpayne@69: ** The update hook implementation must not do anything that will modify jpayne@69: ** the database connection that invoked the update hook. Any actions jpayne@69: ** to modify the database connection must be deferred until after the jpayne@69: ** completion of the [sqlite3_step()] call that triggered the update hook. jpayne@69: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their jpayne@69: ** database connections for the meaning of "modify" in this paragraph. jpayne@69: ** jpayne@69: ** ^The sqlite3_update_hook(D,C,P) function jpayne@69: ** returns the P argument from the previous call jpayne@69: ** on the same [database connection] D, or NULL for jpayne@69: ** the first call on D. jpayne@69: ** jpayne@69: ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], jpayne@69: ** and [sqlite3_preupdate_hook()] interfaces. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_update_hook( jpayne@69: sqlite3*, jpayne@69: void(*)(void *,int ,char const *,char const *,sqlite3_int64), jpayne@69: void* jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Enable Or Disable Shared Pager Cache jpayne@69: ** jpayne@69: ** ^(This routine enables or disables the sharing of the database cache jpayne@69: ** and schema data structures between [database connection | connections] jpayne@69: ** to the same database. Sharing is enabled if the argument is true jpayne@69: ** and disabled if the argument is false.)^ jpayne@69: ** jpayne@69: ** This interface is omitted if SQLite is compiled with jpayne@69: ** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] jpayne@69: ** compile-time option is recommended because the jpayne@69: ** [use of shared cache mode is discouraged]. jpayne@69: ** jpayne@69: ** ^Cache sharing is enabled and disabled for an entire process. jpayne@69: ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). jpayne@69: ** In prior versions of SQLite, jpayne@69: ** sharing was enabled or disabled for each thread separately. jpayne@69: ** jpayne@69: ** ^(The cache sharing mode set by this interface effects all subsequent jpayne@69: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. jpayne@69: ** Existing database connections continue to use the sharing mode jpayne@69: ** that was in effect at the time they were opened.)^ jpayne@69: ** jpayne@69: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled jpayne@69: ** successfully. An [error code] is returned otherwise.)^ jpayne@69: ** jpayne@69: ** ^Shared cache is disabled by default. It is recommended that it stay jpayne@69: ** that way. In other words, do not use this routine. This interface jpayne@69: ** continues to be provided for historical compatibility, but its use is jpayne@69: ** discouraged. Any use of shared cache is discouraged. If shared cache jpayne@69: ** must be used, it is recommended that shared cache only be enabled for jpayne@69: ** individual database connections using the [sqlite3_open_v2()] interface jpayne@69: ** with the [SQLITE_OPEN_SHAREDCACHE] flag. jpayne@69: ** jpayne@69: ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 jpayne@69: ** and will always return SQLITE_MISUSE. On those systems, jpayne@69: ** shared cache mode should be enabled per-database connection via jpayne@69: ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. jpayne@69: ** jpayne@69: ** This interface is threadsafe on processors where writing a jpayne@69: ** 32-bit integer is atomic. jpayne@69: ** jpayne@69: ** See Also: [SQLite Shared-Cache Mode] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_enable_shared_cache(int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Attempt To Free Heap Memory jpayne@69: ** jpayne@69: ** ^The sqlite3_release_memory() interface attempts to free N bytes jpayne@69: ** of heap memory by deallocating non-essential memory allocations jpayne@69: ** held by the database library. Memory used to cache database jpayne@69: ** pages to improve performance is an example of non-essential memory. jpayne@69: ** ^sqlite3_release_memory() returns the number of bytes actually freed, jpayne@69: ** which might be more or less than the amount requested. jpayne@69: ** ^The sqlite3_release_memory() routine is a no-op returning zero jpayne@69: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_db_release_memory()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_release_memory(int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Free Memory Used By A Database Connection jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap jpayne@69: ** memory as possible from database connection D. Unlike the jpayne@69: ** [sqlite3_release_memory()] interface, this interface is in effect even jpayne@69: ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is jpayne@69: ** omitted. jpayne@69: ** jpayne@69: ** See also: [sqlite3_release_memory()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_db_release_memory(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Impose A Limit On Heap Size jpayne@69: ** jpayne@69: ** These interfaces impose limits on the amount of heap memory that will be jpayne@69: ** by all database connections within a single process. jpayne@69: ** jpayne@69: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the jpayne@69: ** soft limit on the amount of heap memory that may be allocated by SQLite. jpayne@69: ** ^SQLite strives to keep heap memory utilization below the soft heap jpayne@69: ** limit by reducing the number of pages held in the page cache jpayne@69: ** as heap memory usages approaches the limit. jpayne@69: ** ^The soft heap limit is "soft" because even though SQLite strives to stay jpayne@69: ** below the limit, it will exceed the limit rather than generate jpayne@69: ** an [SQLITE_NOMEM] error. In other words, the soft heap limit jpayne@69: ** is advisory only. jpayne@69: ** jpayne@69: ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of jpayne@69: ** N bytes on the amount of memory that will be allocated. ^The jpayne@69: ** sqlite3_hard_heap_limit64(N) interface is similar to jpayne@69: ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail jpayne@69: ** when the hard heap limit is reached. jpayne@69: ** jpayne@69: ** ^The return value from both sqlite3_soft_heap_limit64() and jpayne@69: ** sqlite3_hard_heap_limit64() is the size of jpayne@69: ** the heap limit prior to the call, or negative in the case of an jpayne@69: ** error. ^If the argument N is negative jpayne@69: ** then no change is made to the heap limit. Hence, the current jpayne@69: ** size of heap limits can be determined by invoking jpayne@69: ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). jpayne@69: ** jpayne@69: ** ^Setting the heap limits to zero disables the heap limiter mechanism. jpayne@69: ** jpayne@69: ** ^The soft heap limit may not be greater than the hard heap limit. jpayne@69: ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) jpayne@69: ** is invoked with a value of N that is greater than the hard heap limit, jpayne@69: ** the soft heap limit is set to the value of the hard heap limit. jpayne@69: ** ^The soft heap limit is automatically enabled whenever the hard heap jpayne@69: ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and jpayne@69: ** the soft heap limit is outside the range of 1..N, then the soft heap jpayne@69: ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the jpayne@69: ** hard heap limit is enabled makes the soft heap limit equal to the jpayne@69: ** hard heap limit. jpayne@69: ** jpayne@69: ** The memory allocation limits can also be adjusted using jpayne@69: ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. jpayne@69: ** jpayne@69: ** ^(The heap limits are not enforced in the current implementation jpayne@69: ** if one or more of following conditions are true: jpayne@69: ** jpayne@69: ** )^ jpayne@69: ** jpayne@69: ** The circumstances under which SQLite will enforce the heap limits may jpayne@69: ** changes in future releases of SQLite. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); jpayne@69: SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Deprecated Soft Heap Limit Interface jpayne@69: ** DEPRECATED jpayne@69: ** jpayne@69: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] jpayne@69: ** interface. This routine is provided for historical compatibility jpayne@69: ** only. All new applications should use the jpayne@69: ** [sqlite3_soft_heap_limit64()] interface rather than this one. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Extract Metadata About A Column Of A Table jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns jpayne@69: ** information about column C of table T in database D jpayne@69: ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() jpayne@69: ** interface returns SQLITE_OK and fills in the non-NULL pointers in jpayne@69: ** the final five arguments with appropriate values if the specified jpayne@69: ** column exists. ^The sqlite3_table_column_metadata() interface returns jpayne@69: ** SQLITE_ERROR if the specified column does not exist. jpayne@69: ** ^If the column-name parameter to sqlite3_table_column_metadata() is a jpayne@69: ** NULL pointer, then this routine simply checks for the existence of the jpayne@69: ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it jpayne@69: ** does not. If the table name parameter T in a call to jpayne@69: ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is jpayne@69: ** undefined behavior. jpayne@69: ** jpayne@69: ** ^The column is identified by the second, third and fourth parameters to jpayne@69: ** this function. ^(The second parameter is either the name of the database jpayne@69: ** (i.e. "main", "temp", or an attached database) containing the specified jpayne@69: ** table or NULL.)^ ^If it is NULL, then all attached databases are searched jpayne@69: ** for the table using the same algorithm used by the database engine to jpayne@69: ** resolve unqualified table references. jpayne@69: ** jpayne@69: ** ^The third and fourth parameters to this function are the table and column jpayne@69: ** name of the desired column, respectively. jpayne@69: ** jpayne@69: ** ^Metadata is returned by writing to the memory locations passed as the 5th jpayne@69: ** and subsequent parameters to this function. ^Any of these arguments may be jpayne@69: ** NULL, in which case the corresponding element of metadata is omitted. jpayne@69: ** jpayne@69: ** ^(
jpayne@69: ** jpayne@69: **
Parameter Output
Type 		Description jpayne@69: ** jpayne@69: **
5th const char* Data type jpayne@69: **
6th const char* Name of default collation sequence jpayne@69: **
7th int True if column has a NOT NULL constraint jpayne@69: **
8th int True if column is part of the PRIMARY KEY jpayne@69: **
9th int True if column is [AUTOINCREMENT] jpayne@69: **
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^The memory pointed to by the character pointers returned for the jpayne@69: ** declaration type and collation sequence is valid until the next jpayne@69: ** call to any SQLite API function. jpayne@69: ** jpayne@69: ** ^If the specified table is actually a view, an [error code] is returned. jpayne@69: ** jpayne@69: ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table jpayne@69: ** is not a [WITHOUT ROWID] table and an jpayne@69: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output jpayne@69: ** parameters are set for the explicitly declared column. ^(If there is no jpayne@69: ** [INTEGER PRIMARY KEY] column, then the outputs jpayne@69: ** for the [rowid] are set as follows: jpayne@69: ** jpayne@69: ** 
jpayne@69: **     data type: "INTEGER"
jpayne@69: **     collation sequence: "BINARY"
jpayne@69: **     not null: 0
jpayne@69: **     primary key: 1
jpayne@69: **     auto increment: 0
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^This function causes all database schemas to be read from disk and jpayne@69: ** parsed, if that has not already been done, and returns an error if jpayne@69: ** any errors are encountered while loading the schema. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_table_column_metadata( jpayne@69: sqlite3 *db, /* Connection handle */ jpayne@69: const char *zDbName, /* Database name or NULL */ jpayne@69: const char *zTableName, /* Table name */ jpayne@69: const char *zColumnName, /* Column name */ jpayne@69: char const **pzDataType, /* OUTPUT: Declared data type */ jpayne@69: char const **pzCollSeq, /* OUTPUT: Collation sequence name */ jpayne@69: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ jpayne@69: int *pPrimaryKey, /* OUTPUT: True if column part of PK */ jpayne@69: int *pAutoinc /* OUTPUT: True if column is auto-increment */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Load An Extension jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This interface loads an SQLite extension library from the named file. jpayne@69: ** jpayne@69: ** ^The sqlite3_load_extension() interface attempts to load an jpayne@69: ** [SQLite extension] library contained in the file zFile. If jpayne@69: ** the file cannot be loaded directly, attempts are made to load jpayne@69: ** with various operating-system specific extensions added. jpayne@69: ** So for example, if "samplelib" cannot be loaded, then names like jpayne@69: ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might jpayne@69: ** be tried also. jpayne@69: ** jpayne@69: ** ^The entry point is zProc. jpayne@69: ** ^(zProc may be 0, in which case SQLite will try to come up with an jpayne@69: ** entry point name on its own. It first tries "sqlite3_extension_init". jpayne@69: ** If that does not work, it constructs a name "sqlite3_X_init" where the jpayne@69: ** X is consists of the lower-case equivalent of all ASCII alphabetic jpayne@69: ** characters in the filename from the last "/" to the first following jpayne@69: ** "." and omitting any initial "lib".)^ jpayne@69: ** ^The sqlite3_load_extension() interface returns jpayne@69: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. jpayne@69: ** ^If an error occurs and pzErrMsg is not 0, then the jpayne@69: ** [sqlite3_load_extension()] interface shall attempt to jpayne@69: ** fill *pzErrMsg with error message text stored in memory jpayne@69: ** obtained from [sqlite3_malloc()]. The calling function jpayne@69: ** should free this memory by calling [sqlite3_free()]. jpayne@69: ** jpayne@69: ** ^Extension loading must be enabled using jpayne@69: ** [sqlite3_enable_load_extension()] or jpayne@69: ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) jpayne@69: ** prior to calling this API, jpayne@69: ** otherwise an error will be returned. jpayne@69: ** jpayne@69: ** Security warning: It is recommended that the jpayne@69: ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this jpayne@69: ** interface. The use of the [sqlite3_enable_load_extension()] interface jpayne@69: ** should be avoided. This will keep the SQL function [load_extension()] jpayne@69: ** disabled and prevent SQL injections from giving attackers jpayne@69: ** access to extension loading capabilities. jpayne@69: ** jpayne@69: ** See also the [load_extension() SQL function]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_load_extension( jpayne@69: sqlite3 *db, /* Load the extension into this database connection */ jpayne@69: const char *zFile, /* Name of the shared library containing extension */ jpayne@69: const char *zProc, /* Entry point. Derived from zFile if 0 */ jpayne@69: char **pzErrMsg /* Put error message here if not 0 */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Enable Or Disable Extension Loading jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^So as not to open security holes in older applications that are jpayne@69: ** unprepared to deal with [extension loading], and as a means of disabling jpayne@69: ** [extension loading] while evaluating user-entered SQL, the following API jpayne@69: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. jpayne@69: ** jpayne@69: ** ^Extension loading is off by default. jpayne@69: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 jpayne@69: ** to turn extension loading on and call it with onoff==0 to turn jpayne@69: ** it back off again. jpayne@69: ** jpayne@69: ** ^This interface enables or disables both the C-API jpayne@69: ** [sqlite3_load_extension()] and the SQL function [load_extension()]. jpayne@69: ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) jpayne@69: ** to enable or disable only the C-API.)^ jpayne@69: ** jpayne@69: ** Security warning: It is recommended that extension loading jpayne@69: ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method jpayne@69: ** rather than this interface, so the [load_extension()] SQL function jpayne@69: ** remains disabled. This will prevent SQL injections from giving attackers jpayne@69: ** access to extension loading capabilities. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Automatically Load Statically Linked Extensions jpayne@69: ** jpayne@69: ** ^This interface causes the xEntryPoint() function to be invoked for jpayne@69: ** each new [database connection] that is created. The idea here is that jpayne@69: ** xEntryPoint() is the entry point for a statically linked [SQLite extension] jpayne@69: ** that is to be automatically loaded into all new database connections. jpayne@69: ** jpayne@69: ** ^(Even though the function prototype shows that xEntryPoint() takes jpayne@69: ** no arguments and returns void, SQLite invokes xEntryPoint() with three jpayne@69: ** arguments and expects an integer result as if the signature of the jpayne@69: ** entry point where as follows: jpayne@69: ** jpayne@69: ** 
jpayne@69: **    int xEntryPoint(
jpayne@69: **      sqlite3 *db,
jpayne@69: **      const char **pzErrMsg,
jpayne@69: **      const struct sqlite3_api_routines *pThunk
jpayne@69: **    );
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg jpayne@69: ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) jpayne@69: ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg jpayne@69: ** is NULL before calling the xEntryPoint(). ^SQLite will invoke jpayne@69: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any jpayne@69: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], jpayne@69: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. jpayne@69: ** jpayne@69: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already jpayne@69: ** on the list of automatic extensions is a harmless no-op. ^No entry point jpayne@69: ** will be called more than once for each database connection that is opened. jpayne@69: ** jpayne@69: ** See also: [sqlite3_reset_auto_extension()] jpayne@69: ** and [sqlite3_cancel_auto_extension()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Cancel Automatic Extension Loading jpayne@69: ** jpayne@69: ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the jpayne@69: ** initialization routine X that was registered using a prior call to jpayne@69: ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] jpayne@69: ** routine returns 1 if initialization routine X was successfully jpayne@69: ** unregistered and it returns 0 if X was not on the list of initialization jpayne@69: ** routines. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Reset Automatic Extension Loading jpayne@69: ** jpayne@69: ** ^This interface disables all automatic extensions previously jpayne@69: ** registered using [sqlite3_auto_extension()]. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_reset_auto_extension(void); jpayne@69: jpayne@69: /* jpayne@69: ** Structures used by the virtual table interface jpayne@69: */ jpayne@69: typedef struct sqlite3_vtab sqlite3_vtab; jpayne@69: typedef struct sqlite3_index_info sqlite3_index_info; jpayne@69: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; jpayne@69: typedef struct sqlite3_module sqlite3_module; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Object jpayne@69: ** KEYWORDS: sqlite3_module {virtual table module} jpayne@69: ** jpayne@69: ** This structure, sometimes called a "virtual table module", jpayne@69: ** defines the implementation of a [virtual table]. jpayne@69: ** This structure consists mostly of methods for the module. jpayne@69: ** jpayne@69: ** ^A virtual table module is created by filling in a persistent jpayne@69: ** instance of this structure and passing a pointer to that instance jpayne@69: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. jpayne@69: ** ^The registration remains valid until it is replaced by a different jpayne@69: ** module or until the [database connection] closes. The content jpayne@69: ** of this structure must not change while it is registered with jpayne@69: ** any database connection. jpayne@69: */ jpayne@69: struct sqlite3_module { jpayne@69: int iVersion; jpayne@69: int (*xCreate)(sqlite3*, void *pAux, jpayne@69: int argc, const char *const*argv, jpayne@69: sqlite3_vtab **ppVTab, char**); jpayne@69: int (*xConnect)(sqlite3*, void *pAux, jpayne@69: int argc, const char *const*argv, jpayne@69: sqlite3_vtab **ppVTab, char**); jpayne@69: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); jpayne@69: int (*xDisconnect)(sqlite3_vtab *pVTab); jpayne@69: int (*xDestroy)(sqlite3_vtab *pVTab); jpayne@69: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); jpayne@69: int (*xClose)(sqlite3_vtab_cursor*); jpayne@69: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, jpayne@69: int argc, sqlite3_value **argv); jpayne@69: int (*xNext)(sqlite3_vtab_cursor*); jpayne@69: int (*xEof)(sqlite3_vtab_cursor*); jpayne@69: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); jpayne@69: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); jpayne@69: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); jpayne@69: int (*xBegin)(sqlite3_vtab *pVTab); jpayne@69: int (*xSync)(sqlite3_vtab *pVTab); jpayne@69: int (*xCommit)(sqlite3_vtab *pVTab); jpayne@69: int (*xRollback)(sqlite3_vtab *pVTab); jpayne@69: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, jpayne@69: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), jpayne@69: void **ppArg); jpayne@69: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); jpayne@69: /* The methods above are in version 1 of the sqlite_module object. Those jpayne@69: ** below are for version 2 and greater. */ jpayne@69: int (*xSavepoint)(sqlite3_vtab *pVTab, int); jpayne@69: int (*xRelease)(sqlite3_vtab *pVTab, int); jpayne@69: int (*xRollbackTo)(sqlite3_vtab *pVTab, int); jpayne@69: /* The methods above are in versions 1 and 2 of the sqlite_module object. jpayne@69: ** Those below are for version 3 and greater. */ jpayne@69: int (*xShadowName)(const char*); jpayne@69: /* The methods above are in versions 1 through 3 of the sqlite_module object. jpayne@69: ** Those below are for version 4 and greater. */ jpayne@69: int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema, jpayne@69: const char *zTabName, int mFlags, char **pzErr); jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Indexing Information jpayne@69: ** KEYWORDS: sqlite3_index_info jpayne@69: ** jpayne@69: ** The sqlite3_index_info structure and its substructures is used as part jpayne@69: ** of the [virtual table] interface to jpayne@69: ** pass information into and receive the reply from the [xBestIndex] jpayne@69: ** method of a [virtual table module]. The fields under **Inputs** are the jpayne@69: ** inputs to xBestIndex and are read-only. xBestIndex inserts its jpayne@69: ** results into the **Outputs** fields. jpayne@69: ** jpayne@69: ** ^(The aConstraint[] array records WHERE clause constraints of the form: jpayne@69: ** jpayne@69: **
column OP expr
jpayne@69: ** jpayne@69: ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is jpayne@69: ** stored in aConstraint[].op using one of the jpayne@69: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ jpayne@69: ** ^(The index of the column is stored in jpayne@69: ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the jpayne@69: ** expr on the right-hand side can be evaluated (and thus the constraint jpayne@69: ** is usable) and false if it cannot.)^ jpayne@69: ** jpayne@69: ** ^The optimizer automatically inverts terms of the form "expr OP column" jpayne@69: ** and makes other simplifications to the WHERE clause in an attempt to jpayne@69: ** get as many WHERE clause terms into the form shown above as possible. jpayne@69: ** ^The aConstraint[] array only reports WHERE clause terms that are jpayne@69: ** relevant to the particular virtual table being queried. jpayne@69: ** jpayne@69: ** ^Information about the ORDER BY clause is stored in aOrderBy[]. jpayne@69: ** ^Each term of aOrderBy records a column of the ORDER BY clause. jpayne@69: ** jpayne@69: ** The colUsed field indicates which columns of the virtual table may be jpayne@69: ** required by the current scan. Virtual table columns are numbered from jpayne@69: ** zero in the order in which they appear within the CREATE TABLE statement jpayne@69: ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), jpayne@69: ** the corresponding bit is set within the colUsed mask if the column may be jpayne@69: ** required by SQLite. If the table has at least 64 columns and any column jpayne@69: ** to the right of the first 63 is required, then bit 63 of colUsed is also jpayne@69: ** set. In other words, column iCol may be required if the expression jpayne@69: ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to jpayne@69: ** non-zero. jpayne@69: ** jpayne@69: ** The [xBestIndex] method must fill aConstraintUsage[] with information jpayne@69: ** about what parameters to pass to xFilter. ^If argvIndex>0 then jpayne@69: ** the right-hand side of the corresponding aConstraint[] is evaluated jpayne@69: ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit jpayne@69: ** is true, then the constraint is assumed to be fully handled by the jpayne@69: ** virtual table and might not be checked again by the byte code.)^ ^(The jpayne@69: ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag jpayne@69: ** is left in its default setting of false, the constraint will always be jpayne@69: ** checked separately in byte code. If the omit flag is change to true, then jpayne@69: ** the constraint may or may not be checked in byte code. In other words, jpayne@69: ** when the omit flag is true there is no guarantee that the constraint will jpayne@69: ** not be checked again using byte code.)^ jpayne@69: ** jpayne@69: ** ^The idxNum and idxStr values are recorded and passed into the jpayne@69: ** [xFilter] method. jpayne@69: ** ^[sqlite3_free()] is used to free idxStr if and only if jpayne@69: ** needToFreeIdxStr is true. jpayne@69: ** jpayne@69: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in jpayne@69: ** the correct order to satisfy the ORDER BY clause so that no separate jpayne@69: ** sorting step is required. jpayne@69: ** jpayne@69: ** ^The estimatedCost value is an estimate of the cost of a particular jpayne@69: ** strategy. A cost of N indicates that the cost of the strategy is similar jpayne@69: ** to a linear scan of an SQLite table with N rows. A cost of log(N) jpayne@69: ** indicates that the expense of the operation is similar to that of a jpayne@69: ** binary search on a unique indexed field of an SQLite table with N rows. jpayne@69: ** jpayne@69: ** ^The estimatedRows value is an estimate of the number of rows that jpayne@69: ** will be returned by the strategy. jpayne@69: ** jpayne@69: ** The xBestIndex method may optionally populate the idxFlags field with a jpayne@69: ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - jpayne@69: ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite jpayne@69: ** assumes that the strategy may visit at most one row. jpayne@69: ** jpayne@69: ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then jpayne@69: ** SQLite also assumes that if a call to the xUpdate() method is made as jpayne@69: ** part of the same statement to delete or update a virtual table row and the jpayne@69: ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback jpayne@69: ** any database changes. In other words, if the xUpdate() returns jpayne@69: ** SQLITE_CONSTRAINT, the database contents must be exactly as they were jpayne@69: ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not jpayne@69: ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by jpayne@69: ** the xUpdate method are automatically rolled back by SQLite. jpayne@69: ** jpayne@69: ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info jpayne@69: ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). jpayne@69: ** If a virtual table extension is jpayne@69: ** used with an SQLite version earlier than 3.8.2, the results of attempting jpayne@69: ** to read or write the estimatedRows field are undefined (but are likely jpayne@69: ** to include crashing the application). The estimatedRows field should jpayne@69: ** therefore only be used if [sqlite3_libversion_number()] returns a jpayne@69: ** value greater than or equal to 3008002. Similarly, the idxFlags field jpayne@69: ** was added for [version 3.9.0] ([dateof:3.9.0]). jpayne@69: ** It may therefore only be used if jpayne@69: ** sqlite3_libversion_number() returns a value greater than or equal to jpayne@69: ** 3009000. jpayne@69: */ jpayne@69: struct sqlite3_index_info { jpayne@69: /* Inputs */ jpayne@69: int nConstraint; /* Number of entries in aConstraint */ jpayne@69: struct sqlite3_index_constraint { jpayne@69: int iColumn; /* Column constrained. -1 for ROWID */ jpayne@69: unsigned char op; /* Constraint operator */ jpayne@69: unsigned char usable; /* True if this constraint is usable */ jpayne@69: int iTermOffset; /* Used internally - xBestIndex should ignore */ jpayne@69: } *aConstraint; /* Table of WHERE clause constraints */ jpayne@69: int nOrderBy; /* Number of terms in the ORDER BY clause */ jpayne@69: struct sqlite3_index_orderby { jpayne@69: int iColumn; /* Column number */ jpayne@69: unsigned char desc; /* True for DESC. False for ASC. */ jpayne@69: } *aOrderBy; /* The ORDER BY clause */ jpayne@69: /* Outputs */ jpayne@69: struct sqlite3_index_constraint_usage { jpayne@69: int argvIndex; /* if >0, constraint is part of argv to xFilter */ jpayne@69: unsigned char omit; /* Do not code a test for this constraint */ jpayne@69: } *aConstraintUsage; jpayne@69: int idxNum; /* Number used to identify the index */ jpayne@69: char *idxStr; /* String, possibly obtained from sqlite3_malloc */ jpayne@69: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ jpayne@69: int orderByConsumed; /* True if output is already ordered */ jpayne@69: double estimatedCost; /* Estimated cost of using this index */ jpayne@69: /* Fields below are only available in SQLite 3.8.2 and later */ jpayne@69: sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ jpayne@69: /* Fields below are only available in SQLite 3.9.0 and later */ jpayne@69: int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ jpayne@69: /* Fields below are only available in SQLite 3.10.0 and later */ jpayne@69: sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Scan Flags jpayne@69: ** jpayne@69: ** Virtual table implementations are allowed to set the jpayne@69: ** [sqlite3_index_info].idxFlags field to some combination of jpayne@69: ** these bits. jpayne@69: */ jpayne@69: #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Constraint Operator Codes jpayne@69: ** jpayne@69: ** These macros define the allowed values for the jpayne@69: ** [sqlite3_index_info].aConstraint[].op field. Each value represents jpayne@69: ** an operator that is part of a constraint term in the WHERE clause of jpayne@69: ** a query that uses a [virtual table]. jpayne@69: ** jpayne@69: ** ^The left-hand operand of the operator is given by the corresponding jpayne@69: ** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand jpayne@69: ** operand is the rowid. jpayne@69: ** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET jpayne@69: ** operators have no left-hand operand, and so for those operators the jpayne@69: ** corresponding aConstraint[].iColumn is meaningless and should not be jpayne@69: ** used. jpayne@69: ** jpayne@69: ** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through jpayne@69: ** value 255 are reserved to represent functions that are overloaded jpayne@69: ** by the [xFindFunction|xFindFunction method] of the virtual table jpayne@69: ** implementation. jpayne@69: ** jpayne@69: ** The right-hand operands for each constraint might be accessible using jpayne@69: ** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand jpayne@69: ** operand is only available if it appears as a single constant literal jpayne@69: ** in the input SQL. If the right-hand operand is another column or an jpayne@69: ** expression (even a constant expression) or a parameter, then the jpayne@69: ** sqlite3_vtab_rhs_value() probably will not be able to extract it. jpayne@69: ** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and jpayne@69: ** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand jpayne@69: ** and hence calls to sqlite3_vtab_rhs_value() for those operators will jpayne@69: ** always return SQLITE_NOTFOUND. jpayne@69: ** jpayne@69: ** The collating sequence to be used for comparison can be found using jpayne@69: ** the [sqlite3_vtab_collation()] interface. For most real-world virtual jpayne@69: ** tables, the collating sequence of constraints does not matter (for example jpayne@69: ** because the constraints are numeric) and so the sqlite3_vtab_collation() jpayne@69: ** interface is not commonly needed. jpayne@69: */ jpayne@69: #define SQLITE_INDEX_CONSTRAINT_EQ 2 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_GT 4 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_LE 8 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_LT 16 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_GE 32 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_MATCH 64 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_LIKE 65 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_GLOB 66 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_NE 68 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_IS 72 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_LIMIT 73 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_OFFSET 74 jpayne@69: #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Register A Virtual Table Implementation jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These routines are used to register a new [virtual table module] name. jpayne@69: ** ^Module names must be registered before jpayne@69: ** creating a new [virtual table] using the module and before using a jpayne@69: ** preexisting [virtual table] for the module. jpayne@69: ** jpayne@69: ** ^The module name is registered on the [database connection] specified jpayne@69: ** by the first parameter. ^The name of the module is given by the jpayne@69: ** second parameter. ^The third parameter is a pointer to jpayne@69: ** the implementation of the [virtual table module]. ^The fourth jpayne@69: ** parameter is an arbitrary client data pointer that is passed through jpayne@69: ** into the [xCreate] and [xConnect] methods of the virtual table module jpayne@69: ** when a new virtual table is be being created or reinitialized. jpayne@69: ** jpayne@69: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which jpayne@69: ** is a pointer to a destructor for the pClientData. ^SQLite will jpayne@69: ** invoke the destructor function (if it is not NULL) when SQLite jpayne@69: ** no longer needs the pClientData pointer. ^The destructor will also jpayne@69: ** be invoked if the call to sqlite3_create_module_v2() fails. jpayne@69: ** ^The sqlite3_create_module() jpayne@69: ** interface is equivalent to sqlite3_create_module_v2() with a NULL jpayne@69: ** destructor. jpayne@69: ** jpayne@69: ** ^If the third parameter (the pointer to the sqlite3_module object) is jpayne@69: ** NULL then no new module is created and any existing modules with the jpayne@69: ** same name are dropped. jpayne@69: ** jpayne@69: ** See also: [sqlite3_drop_modules()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_create_module( jpayne@69: sqlite3 *db, /* SQLite connection to register module with */ jpayne@69: const char *zName, /* Name of the module */ jpayne@69: const sqlite3_module *p, /* Methods for the module */ jpayne@69: void *pClientData /* Client data for xCreate/xConnect */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_create_module_v2( jpayne@69: sqlite3 *db, /* SQLite connection to register module with */ jpayne@69: const char *zName, /* Name of the module */ jpayne@69: const sqlite3_module *p, /* Methods for the module */ jpayne@69: void *pClientData, /* Client data for xCreate/xConnect */ jpayne@69: void(*xDestroy)(void*) /* Module destructor function */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Remove Unnecessary Virtual Table Implementations jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The sqlite3_drop_modules(D,L) interface removes all virtual jpayne@69: ** table modules from database connection D except those named on list L. jpayne@69: ** The L parameter must be either NULL or a pointer to an array of pointers jpayne@69: ** to strings where the array is terminated by a single NULL pointer. jpayne@69: ** ^If the L parameter is NULL, then all virtual table modules are removed. jpayne@69: ** jpayne@69: ** See also: [sqlite3_create_module()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_drop_modules( jpayne@69: sqlite3 *db, /* Remove modules from this connection */ jpayne@69: const char **azKeep /* Except, do not remove the ones named here */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Instance Object jpayne@69: ** KEYWORDS: sqlite3_vtab jpayne@69: ** jpayne@69: ** Every [virtual table module] implementation uses a subclass jpayne@69: ** of this object to describe a particular instance jpayne@69: ** of the [virtual table]. Each subclass will jpayne@69: ** be tailored to the specific needs of the module implementation. jpayne@69: ** The purpose of this superclass is to define certain fields that are jpayne@69: ** common to all module implementations. jpayne@69: ** jpayne@69: ** ^Virtual tables methods can set an error message by assigning a jpayne@69: ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should jpayne@69: ** take care that any prior string is freed by a call to [sqlite3_free()] jpayne@69: ** prior to assigning a new string to zErrMsg. ^After the error message jpayne@69: ** is delivered up to the client application, the string will be automatically jpayne@69: ** freed by sqlite3_free() and the zErrMsg field will be zeroed. jpayne@69: */ jpayne@69: struct sqlite3_vtab { jpayne@69: const sqlite3_module *pModule; /* The module for this virtual table */ jpayne@69: int nRef; /* Number of open cursors */ jpayne@69: char *zErrMsg; /* Error message from sqlite3_mprintf() */ jpayne@69: /* Virtual table implementations will typically add additional fields */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Cursor Object jpayne@69: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} jpayne@69: ** jpayne@69: ** Every [virtual table module] implementation uses a subclass of the jpayne@69: ** following structure to describe cursors that point into the jpayne@69: ** [virtual table] and are used jpayne@69: ** to loop through the virtual table. Cursors are created using the jpayne@69: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed jpayne@69: ** by the [sqlite3_module.xClose | xClose] method. Cursors are used jpayne@69: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods jpayne@69: ** of the module. Each module implementation will define jpayne@69: ** the content of a cursor structure to suit its own needs. jpayne@69: ** jpayne@69: ** This superclass exists in order to define fields of the cursor that jpayne@69: ** are common to all implementations. jpayne@69: */ jpayne@69: struct sqlite3_vtab_cursor { jpayne@69: sqlite3_vtab *pVtab; /* Virtual table of this cursor */ jpayne@69: /* Virtual table implementations will typically add additional fields */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Declare The Schema Of A Virtual Table jpayne@69: ** jpayne@69: ** ^The [xCreate] and [xConnect] methods of a jpayne@69: ** [virtual table module] call this interface jpayne@69: ** to declare the format (the names and datatypes of the columns) of jpayne@69: ** the virtual tables they implement. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Overload A Function For A Virtual Table jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^(Virtual tables can provide alternative implementations of functions jpayne@69: ** using the [xFindFunction] method of the [virtual table module]. jpayne@69: ** But global versions of those functions jpayne@69: ** must exist in order to be overloaded.)^ jpayne@69: ** jpayne@69: ** ^(This API makes sure a global version of a function with a particular jpayne@69: ** name and number of parameters exists. If no such function exists jpayne@69: ** before this API is called, a new function is created.)^ ^The implementation jpayne@69: ** of the new function always causes an exception to be thrown. So jpayne@69: ** the new function is not good for anything by itself. Its only jpayne@69: ** purpose is to be a placeholder function that can be overloaded jpayne@69: ** by a [virtual table]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: A Handle To An Open BLOB jpayne@69: ** KEYWORDS: {BLOB handle} {BLOB handles} jpayne@69: ** jpayne@69: ** An instance of this object represents an open BLOB on which jpayne@69: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. jpayne@69: ** ^Objects of this type are created by [sqlite3_blob_open()] jpayne@69: ** and destroyed by [sqlite3_blob_close()]. jpayne@69: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces jpayne@69: ** can be used to read or write small subsections of the BLOB. jpayne@69: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. jpayne@69: */ jpayne@69: typedef struct sqlite3_blob sqlite3_blob; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Open A BLOB For Incremental I/O jpayne@69: ** METHOD: sqlite3 jpayne@69: ** CONSTRUCTOR: sqlite3_blob jpayne@69: ** jpayne@69: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located jpayne@69: ** in row iRow, column zColumn, table zTable in database zDb; jpayne@69: ** in other words, the same BLOB that would be selected by: jpayne@69: ** jpayne@69: ** 
jpayne@69: **     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^(Parameter zDb is not the filename that contains the database, but jpayne@69: ** rather the symbolic name of the database. For attached databases, this is jpayne@69: ** the name that appears after the AS keyword in the [ATTACH] statement. jpayne@69: ** For the main database file, the database name is "main". For TEMP jpayne@69: ** tables, the database name is "temp".)^ jpayne@69: ** jpayne@69: ** ^If the flags parameter is non-zero, then the BLOB is opened for read jpayne@69: ** and write access. ^If the flags parameter is zero, the BLOB is opened for jpayne@69: ** read-only access. jpayne@69: ** jpayne@69: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored jpayne@69: ** in *ppBlob. Otherwise an [error code] is returned and, unless the error jpayne@69: ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided jpayne@69: ** the API is not misused, it is always safe to call [sqlite3_blob_close()] jpayne@69: ** on *ppBlob after this function it returns. jpayne@69: ** jpayne@69: ** This function fails with SQLITE_ERROR if any of the following are true: jpayne@69: ** jpayne@69: ** jpayne@69: ** ^Unless it returns SQLITE_MISUSE, this function sets the jpayne@69: ** [database connection] error code and message accessible via jpayne@69: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. jpayne@69: ** jpayne@69: ** A BLOB referenced by sqlite3_blob_open() may be read using the jpayne@69: ** [sqlite3_blob_read()] interface and modified by using jpayne@69: ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a jpayne@69: ** different row of the same table using the [sqlite3_blob_reopen()] jpayne@69: ** interface. However, the column, table, or database of a [BLOB handle] jpayne@69: ** cannot be changed after the [BLOB handle] is opened. jpayne@69: ** jpayne@69: ** ^(If the row that a BLOB handle points to is modified by an jpayne@69: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects jpayne@69: ** then the BLOB handle is marked as "expired". jpayne@69: ** This is true if any column of the row is changed, even a column jpayne@69: ** other than the one the BLOB handle is open on.)^ jpayne@69: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for jpayne@69: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. jpayne@69: ** ^(Changes written into a BLOB prior to the BLOB expiring are not jpayne@69: ** rolled back by the expiration of the BLOB. Such changes will eventually jpayne@69: ** commit if the transaction continues to completion.)^ jpayne@69: ** jpayne@69: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of jpayne@69: ** the opened blob. ^The size of a blob may not be changed by this jpayne@69: ** interface. Use the [UPDATE] SQL command to change the size of a jpayne@69: ** blob. jpayne@69: ** jpayne@69: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces jpayne@69: ** and the built-in [zeroblob] SQL function may be used to create a jpayne@69: ** zero-filled blob to read or write using the incremental-blob interface. jpayne@69: ** jpayne@69: ** To avoid a resource leak, every open [BLOB handle] should eventually jpayne@69: ** be released by a call to [sqlite3_blob_close()]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_blob_close()], jpayne@69: ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], jpayne@69: ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_open( jpayne@69: sqlite3*, jpayne@69: const char *zDb, jpayne@69: const char *zTable, jpayne@69: const char *zColumn, jpayne@69: sqlite3_int64 iRow, jpayne@69: int flags, jpayne@69: sqlite3_blob **ppBlob jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Move a BLOB Handle to a New Row jpayne@69: ** METHOD: sqlite3_blob jpayne@69: ** jpayne@69: ** ^This function is used to move an existing [BLOB handle] so that it points jpayne@69: ** to a different row of the same database table. ^The new row is identified jpayne@69: ** by the rowid value passed as the second argument. Only the row can be jpayne@69: ** changed. ^The database, table and column on which the blob handle is open jpayne@69: ** remain the same. Moving an existing [BLOB handle] to a new row is jpayne@69: ** faster than closing the existing handle and opening a new one. jpayne@69: ** jpayne@69: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - jpayne@69: ** it must exist and there must be either a blob or text value stored in jpayne@69: ** the nominated column.)^ ^If the new row is not present in the table, or if jpayne@69: ** it does not contain a blob or text value, or if another error occurs, an jpayne@69: ** SQLite error code is returned and the blob handle is considered aborted. jpayne@69: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or jpayne@69: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return jpayne@69: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle jpayne@69: ** always returns zero. jpayne@69: ** jpayne@69: ** ^This function sets the database handle error code and message. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Close A BLOB Handle jpayne@69: ** DESTRUCTOR: sqlite3_blob jpayne@69: ** jpayne@69: ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed jpayne@69: ** unconditionally. Even if this routine returns an error code, the jpayne@69: ** handle is still closed.)^ jpayne@69: ** jpayne@69: ** ^If the blob handle being closed was opened for read-write access, and if jpayne@69: ** the database is in auto-commit mode and there are no other open read-write jpayne@69: ** blob handles or active write statements, the current transaction is jpayne@69: ** committed. ^If an error occurs while committing the transaction, an error jpayne@69: ** code is returned and the transaction rolled back. jpayne@69: ** jpayne@69: ** Calling this function with an argument that is not a NULL pointer or an jpayne@69: ** open blob handle results in undefined behavior. ^Calling this routine jpayne@69: ** with a null pointer (such as would be returned by a failed call to jpayne@69: ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function jpayne@69: ** is passed a valid open blob handle, the values returned by the jpayne@69: ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_close(sqlite3_blob *); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Return The Size Of An Open BLOB jpayne@69: ** METHOD: sqlite3_blob jpayne@69: ** jpayne@69: ** ^Returns the size in bytes of the BLOB accessible via the jpayne@69: ** successfully opened [BLOB handle] in its only argument. ^The jpayne@69: ** incremental blob I/O routines can only read or overwriting existing jpayne@69: ** blob content; they cannot change the size of a blob. jpayne@69: ** jpayne@69: ** This routine only works on a [BLOB handle] which has been created jpayne@69: ** by a prior successful call to [sqlite3_blob_open()] and which has not jpayne@69: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in jpayne@69: ** to this routine results in undefined and probably undesirable behavior. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Read Data From A BLOB Incrementally jpayne@69: ** METHOD: sqlite3_blob jpayne@69: ** jpayne@69: ** ^(This function is used to read data from an open [BLOB handle] into a jpayne@69: ** caller-supplied buffer. N bytes of data are copied into buffer Z jpayne@69: ** from the open BLOB, starting at offset iOffset.)^ jpayne@69: ** jpayne@69: ** ^If offset iOffset is less than N bytes from the end of the BLOB, jpayne@69: ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is jpayne@69: ** less than zero, [SQLITE_ERROR] is returned and no data is read. jpayne@69: ** ^The size of the blob (and hence the maximum value of N+iOffset) jpayne@69: ** can be determined using the [sqlite3_blob_bytes()] interface. jpayne@69: ** jpayne@69: ** ^An attempt to read from an expired [BLOB handle] fails with an jpayne@69: ** error code of [SQLITE_ABORT]. jpayne@69: ** jpayne@69: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. jpayne@69: ** Otherwise, an [error code] or an [extended error code] is returned.)^ jpayne@69: ** jpayne@69: ** This routine only works on a [BLOB handle] which has been created jpayne@69: ** by a prior successful call to [sqlite3_blob_open()] and which has not jpayne@69: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in jpayne@69: ** to this routine results in undefined and probably undesirable behavior. jpayne@69: ** jpayne@69: ** See also: [sqlite3_blob_write()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Write Data Into A BLOB Incrementally jpayne@69: ** METHOD: sqlite3_blob jpayne@69: ** jpayne@69: ** ^(This function is used to write data into an open [BLOB handle] from a jpayne@69: ** caller-supplied buffer. N bytes of data are copied from the buffer Z jpayne@69: ** into the open BLOB, starting at offset iOffset.)^ jpayne@69: ** jpayne@69: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. jpayne@69: ** Otherwise, an [error code] or an [extended error code] is returned.)^ jpayne@69: ** ^Unless SQLITE_MISUSE is returned, this function sets the jpayne@69: ** [database connection] error code and message accessible via jpayne@69: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. jpayne@69: ** jpayne@69: ** ^If the [BLOB handle] passed as the first argument was not opened for jpayne@69: ** writing (the flags parameter to [sqlite3_blob_open()] was zero), jpayne@69: ** this function returns [SQLITE_READONLY]. jpayne@69: ** jpayne@69: ** This function may only modify the contents of the BLOB; it is jpayne@69: ** not possible to increase the size of a BLOB using this API. jpayne@69: ** ^If offset iOffset is less than N bytes from the end of the BLOB, jpayne@69: ** [SQLITE_ERROR] is returned and no data is written. The size of the jpayne@69: ** BLOB (and hence the maximum value of N+iOffset) can be determined jpayne@69: ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less jpayne@69: ** than zero [SQLITE_ERROR] is returned and no data is written. jpayne@69: ** jpayne@69: ** ^An attempt to write to an expired [BLOB handle] fails with an jpayne@69: ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred jpayne@69: ** before the [BLOB handle] expired are not rolled back by the jpayne@69: ** expiration of the handle, though of course those changes might jpayne@69: ** have been overwritten by the statement that expired the BLOB handle jpayne@69: ** or by other independent statements. jpayne@69: ** jpayne@69: ** This routine only works on a [BLOB handle] which has been created jpayne@69: ** by a prior successful call to [sqlite3_blob_open()] and which has not jpayne@69: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in jpayne@69: ** to this routine results in undefined and probably undesirable behavior. jpayne@69: ** jpayne@69: ** See also: [sqlite3_blob_read()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual File System Objects jpayne@69: ** jpayne@69: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object jpayne@69: ** that SQLite uses to interact jpayne@69: ** with the underlying operating system. Most SQLite builds come with a jpayne@69: ** single default VFS that is appropriate for the host computer. jpayne@69: ** New VFSes can be registered and existing VFSes can be unregistered. jpayne@69: ** The following interfaces are provided. jpayne@69: ** jpayne@69: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. jpayne@69: ** ^Names are case sensitive. jpayne@69: ** ^Names are zero-terminated UTF-8 strings. jpayne@69: ** ^If there is no match, a NULL pointer is returned. jpayne@69: ** ^If zVfsName is NULL then the default VFS is returned. jpayne@69: ** jpayne@69: ** ^New VFSes are registered with sqlite3_vfs_register(). jpayne@69: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. jpayne@69: ** ^The same VFS can be registered multiple times without injury. jpayne@69: ** ^To make an existing VFS into the default VFS, register it again jpayne@69: ** with the makeDflt flag set. If two different VFSes with the jpayne@69: ** same name are registered, the behavior is undefined. If a jpayne@69: ** VFS is registered with a name that is NULL or an empty string, jpayne@69: ** then the behavior is undefined. jpayne@69: ** jpayne@69: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. jpayne@69: ** ^(If the default VFS is unregistered, another VFS is chosen as jpayne@69: ** the default. The choice for the new VFS is arbitrary.)^ jpayne@69: */ jpayne@69: SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); jpayne@69: SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); jpayne@69: SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Mutexes jpayne@69: ** jpayne@69: ** The SQLite core uses these routines for thread jpayne@69: ** synchronization. Though they are intended for internal jpayne@69: ** use by SQLite, code that links against SQLite is jpayne@69: ** permitted to use any of these routines. jpayne@69: ** jpayne@69: ** The SQLite source code contains multiple implementations jpayne@69: ** of these mutex routines. An appropriate implementation jpayne@69: ** is selected automatically at compile-time. The following jpayne@69: ** implementations are available in the SQLite core: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** The SQLITE_MUTEX_NOOP implementation is a set of routines jpayne@69: ** that does no real locking and is appropriate for use in jpayne@69: ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and jpayne@69: ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix jpayne@69: ** and Windows. jpayne@69: ** jpayne@69: ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor jpayne@69: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex jpayne@69: ** implementation is included with the library. In this case the jpayne@69: ** application must supply a custom mutex implementation using the jpayne@69: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function jpayne@69: ** before calling sqlite3_initialize() or any other public sqlite3_ jpayne@69: ** function that calls sqlite3_initialize(). jpayne@69: ** jpayne@69: ** ^The sqlite3_mutex_alloc() routine allocates a new jpayne@69: ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() jpayne@69: ** routine returns NULL if it is unable to allocate the requested jpayne@69: ** mutex. The argument to sqlite3_mutex_alloc() must one of these jpayne@69: ** integer constants: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) jpayne@69: ** cause sqlite3_mutex_alloc() to create jpayne@69: ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE jpayne@69: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. jpayne@69: ** The mutex implementation does not need to make a distinction jpayne@69: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does jpayne@69: ** not want to. SQLite will only request a recursive mutex in jpayne@69: ** cases where it really needs one. If a faster non-recursive mutex jpayne@69: ** implementation is available on the host platform, the mutex subsystem jpayne@69: ** might return such a mutex in response to SQLITE_MUTEX_FAST. jpayne@69: ** jpayne@69: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other jpayne@69: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return jpayne@69: ** a pointer to a static preexisting mutex. ^Nine static mutexes are jpayne@69: ** used by the current version of SQLite. Future versions of SQLite jpayne@69: ** may add additional static mutexes. Static mutexes are for internal jpayne@69: ** use by SQLite only. Applications that use SQLite mutexes should jpayne@69: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or jpayne@69: ** SQLITE_MUTEX_RECURSIVE. jpayne@69: ** jpayne@69: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST jpayne@69: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() jpayne@69: ** returns a different mutex on every call. ^For the static jpayne@69: ** mutex types, the same mutex is returned on every call that has jpayne@69: ** the same type number. jpayne@69: ** jpayne@69: ** ^The sqlite3_mutex_free() routine deallocates a previously jpayne@69: ** allocated dynamic mutex. Attempting to deallocate a static jpayne@69: ** mutex results in undefined behavior. jpayne@69: ** jpayne@69: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt jpayne@69: ** to enter a mutex. ^If another thread is already within the mutex, jpayne@69: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return jpayne@69: ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] jpayne@69: ** upon successful entry. ^(Mutexes created using jpayne@69: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. jpayne@69: ** In such cases, the jpayne@69: ** mutex must be exited an equal number of times before another thread jpayne@69: ** can enter.)^ If the same thread tries to enter any mutex other jpayne@69: ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. jpayne@69: ** jpayne@69: ** ^(Some systems (for example, Windows 95) do not support the operation jpayne@69: ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() jpayne@69: ** will always return SQLITE_BUSY. In most cases the SQLite core only uses jpayne@69: ** sqlite3_mutex_try() as an optimization, so this is acceptable jpayne@69: ** behavior. The exceptions are unix builds that set the jpayne@69: ** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working jpayne@69: ** sqlite3_mutex_try() is required.)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_mutex_leave() routine exits a mutex that was jpayne@69: ** previously entered by the same thread. The behavior jpayne@69: ** is undefined if the mutex is not currently entered by the jpayne@69: ** calling thread or is not currently allocated. jpayne@69: ** jpayne@69: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), jpayne@69: ** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer, jpayne@69: ** then any of the four routines behaves as a no-op. jpayne@69: ** jpayne@69: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); jpayne@69: SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); jpayne@69: SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); jpayne@69: SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); jpayne@69: SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Mutex Methods Object jpayne@69: ** jpayne@69: ** An instance of this structure defines the low-level routines jpayne@69: ** used to allocate and use mutexes. jpayne@69: ** jpayne@69: ** Usually, the default mutex implementations provided by SQLite are jpayne@69: ** sufficient, however the application has the option of substituting a custom jpayne@69: ** implementation for specialized deployments or systems for which SQLite jpayne@69: ** does not provide a suitable implementation. In this case, the application jpayne@69: ** creates and populates an instance of this structure to pass jpayne@69: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. jpayne@69: ** Additionally, an instance of this structure can be used as an jpayne@69: ** output variable when querying the system for the current mutex jpayne@69: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. jpayne@69: ** jpayne@69: ** ^The xMutexInit method defined by this structure is invoked as jpayne@69: ** part of system initialization by the sqlite3_initialize() function. jpayne@69: ** ^The xMutexInit routine is called by SQLite exactly once for each jpayne@69: ** effective call to [sqlite3_initialize()]. jpayne@69: ** jpayne@69: ** ^The xMutexEnd method defined by this structure is invoked as jpayne@69: ** part of system shutdown by the sqlite3_shutdown() function. The jpayne@69: ** implementation of this method is expected to release all outstanding jpayne@69: ** resources obtained by the mutex methods implementation, especially jpayne@69: ** those obtained by the xMutexInit method. ^The xMutexEnd() jpayne@69: ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. jpayne@69: ** jpayne@69: ** ^(The remaining seven methods defined by this structure (xMutexAlloc, jpayne@69: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and jpayne@69: ** xMutexNotheld) implement the following interfaces (respectively): jpayne@69: ** jpayne@69: ** )^ jpayne@69: ** jpayne@69: ** The only difference is that the public sqlite3_XXX functions enumerated jpayne@69: ** above silently ignore any invocations that pass a NULL pointer instead jpayne@69: ** of a valid mutex handle. The implementations of the methods defined jpayne@69: ** by this structure are not required to handle this case. The results jpayne@69: ** of passing a NULL pointer instead of a valid mutex handle are undefined jpayne@69: ** (i.e. it is acceptable to provide an implementation that segfaults if jpayne@69: ** it is passed a NULL pointer). jpayne@69: ** jpayne@69: ** The xMutexInit() method must be threadsafe. It must be harmless to jpayne@69: ** invoke xMutexInit() multiple times within the same process and without jpayne@69: ** intervening calls to xMutexEnd(). Second and subsequent calls to jpayne@69: ** xMutexInit() must be no-ops. jpayne@69: ** jpayne@69: ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] jpayne@69: ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory jpayne@69: ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite jpayne@69: ** memory allocation for a fast or recursive mutex. jpayne@69: ** jpayne@69: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is jpayne@69: ** called, but only if the prior call to xMutexInit returned SQLITE_OK. jpayne@69: ** If xMutexInit fails in any way, it is expected to clean up after itself jpayne@69: ** prior to returning. jpayne@69: */ jpayne@69: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; jpayne@69: struct sqlite3_mutex_methods { jpayne@69: int (*xMutexInit)(void); jpayne@69: int (*xMutexEnd)(void); jpayne@69: sqlite3_mutex *(*xMutexAlloc)(int); jpayne@69: void (*xMutexFree)(sqlite3_mutex *); jpayne@69: void (*xMutexEnter)(sqlite3_mutex *); jpayne@69: int (*xMutexTry)(sqlite3_mutex *); jpayne@69: void (*xMutexLeave)(sqlite3_mutex *); jpayne@69: int (*xMutexHeld)(sqlite3_mutex *); jpayne@69: int (*xMutexNotheld)(sqlite3_mutex *); jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Mutex Verification Routines jpayne@69: ** jpayne@69: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines jpayne@69: ** are intended for use inside assert() statements. The SQLite core jpayne@69: ** never uses these routines except inside an assert() and applications jpayne@69: ** are advised to follow the lead of the core. The SQLite core only jpayne@69: ** provides implementations for these routines when it is compiled jpayne@69: ** with the SQLITE_DEBUG flag. External mutex implementations jpayne@69: ** are only required to provide these routines if SQLITE_DEBUG is jpayne@69: ** defined and if NDEBUG is not defined. jpayne@69: ** jpayne@69: ** These routines should return true if the mutex in their argument jpayne@69: ** is held or not held, respectively, by the calling thread. jpayne@69: ** jpayne@69: ** The implementation is not required to provide versions of these jpayne@69: ** routines that actually work. If the implementation does not provide working jpayne@69: ** versions of these routines, it should at least provide stubs that always jpayne@69: ** return true so that one does not get spurious assertion failures. jpayne@69: ** jpayne@69: ** If the argument to sqlite3_mutex_held() is a NULL pointer then jpayne@69: ** the routine should return 1. This seems counter-intuitive since jpayne@69: ** clearly the mutex cannot be held if it does not exist. But jpayne@69: ** the reason the mutex does not exist is because the build is not jpayne@69: ** using mutexes. And we do not want the assert() containing the jpayne@69: ** call to sqlite3_mutex_held() to fail, so a non-zero return is jpayne@69: ** the appropriate thing to do. The sqlite3_mutex_notheld() jpayne@69: ** interface should also return 1 when given a NULL pointer. jpayne@69: */ jpayne@69: #ifndef NDEBUG jpayne@69: SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); jpayne@69: SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Mutex Types jpayne@69: ** jpayne@69: ** The [sqlite3_mutex_alloc()] interface takes a single argument jpayne@69: ** which is one of these integer constants. jpayne@69: ** jpayne@69: ** The set of static mutexes may change from one SQLite release to the jpayne@69: ** next. Applications that override the built-in mutex logic must be jpayne@69: ** prepared to accommodate additional static mutexes. jpayne@69: */ jpayne@69: #define SQLITE_MUTEX_FAST 0 jpayne@69: #define SQLITE_MUTEX_RECURSIVE 1 jpayne@69: #define SQLITE_MUTEX_STATIC_MAIN 2 jpayne@69: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ jpayne@69: #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ jpayne@69: #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ jpayne@69: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ jpayne@69: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ jpayne@69: #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ jpayne@69: #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ jpayne@69: #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ jpayne@69: #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ jpayne@69: #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ jpayne@69: #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ jpayne@69: #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ jpayne@69: #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ jpayne@69: jpayne@69: /* Legacy compatibility: */ jpayne@69: #define SQLITE_MUTEX_STATIC_MASTER 2 jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Retrieve the mutex for a database connection jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This interface returns a pointer the [sqlite3_mutex] object that jpayne@69: ** serializes access to the [database connection] given in the argument jpayne@69: ** when the [threading mode] is Serialized. jpayne@69: ** ^If the [threading mode] is Single-thread or Multi-thread then this jpayne@69: ** routine returns a NULL pointer. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Low-Level Control Of Database Files jpayne@69: ** METHOD: sqlite3 jpayne@69: ** KEYWORDS: {file control} jpayne@69: ** jpayne@69: ** ^The [sqlite3_file_control()] interface makes a direct call to the jpayne@69: ** xFileControl method for the [sqlite3_io_methods] object associated jpayne@69: ** with a particular database identified by the second argument. ^The jpayne@69: ** name of the database is "main" for the main database or "temp" for the jpayne@69: ** TEMP database, or the name that appears after the AS keyword for jpayne@69: ** databases that are added using the [ATTACH] SQL command. jpayne@69: ** ^A NULL pointer can be used in place of "main" to refer to the jpayne@69: ** main database file. jpayne@69: ** ^The third and fourth parameters to this routine jpayne@69: ** are passed directly through to the second and third parameters of jpayne@69: ** the xFileControl method. ^The return value of the xFileControl jpayne@69: ** method becomes the return value of this routine. jpayne@69: ** jpayne@69: ** A few opcodes for [sqlite3_file_control()] are handled directly jpayne@69: ** by the SQLite core and never invoke the jpayne@69: ** sqlite3_io_methods.xFileControl method. jpayne@69: ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes jpayne@69: ** a pointer to the underlying [sqlite3_file] object to be written into jpayne@69: ** the space pointed to by the 4th parameter. The jpayne@69: ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns jpayne@69: ** the [sqlite3_file] object associated with the journal file instead of jpayne@69: ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns jpayne@69: ** a pointer to the underlying [sqlite3_vfs] object for the file. jpayne@69: ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter jpayne@69: ** from the pager. jpayne@69: ** jpayne@69: ** ^If the second parameter (zDbName) does not match the name of any jpayne@69: ** open database file, then SQLITE_ERROR is returned. ^This error jpayne@69: ** code is not remembered and will not be recalled by [sqlite3_errcode()] jpayne@69: ** or [sqlite3_errmsg()]. The underlying xFileControl method might jpayne@69: ** also return SQLITE_ERROR. There is no way to distinguish between jpayne@69: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying jpayne@69: ** xFileControl method. jpayne@69: ** jpayne@69: ** See also: [file control opcodes] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Testing Interface jpayne@69: ** jpayne@69: ** ^The sqlite3_test_control() interface is used to read out internal jpayne@69: ** state of SQLite and to inject faults into SQLite for testing jpayne@69: ** purposes. ^The first parameter is an operation code that determines jpayne@69: ** the number, meaning, and operation of all subsequent parameters. jpayne@69: ** jpayne@69: ** This interface is not for use by applications. It exists solely jpayne@69: ** for verifying the correct operation of the SQLite library. Depending jpayne@69: ** on how the SQLite library is compiled, this interface might not exist. jpayne@69: ** jpayne@69: ** The details of the operation codes, their meanings, the parameters jpayne@69: ** they take, and what they do are all subject to change without notice. jpayne@69: ** Unlike most of the SQLite API, this function is not guaranteed to jpayne@69: ** operate consistently from one release to the next. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_test_control(int op, ...); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Testing Interface Operation Codes jpayne@69: ** jpayne@69: ** These constants are the valid operation code parameters used jpayne@69: ** as the first argument to [sqlite3_test_control()]. jpayne@69: ** jpayne@69: ** These parameters and their meanings are subject to change jpayne@69: ** without notice. These values are for testing purposes only. jpayne@69: ** Applications should not use any of these parameters or the jpayne@69: ** [sqlite3_test_control()] interface. jpayne@69: */ jpayne@69: #define SQLITE_TESTCTRL_FIRST 5 jpayne@69: #define SQLITE_TESTCTRL_PRNG_SAVE 5 jpayne@69: #define SQLITE_TESTCTRL_PRNG_RESTORE 6 jpayne@69: #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ jpayne@69: #define SQLITE_TESTCTRL_FK_NO_ACTION 7 jpayne@69: #define SQLITE_TESTCTRL_BITVEC_TEST 8 jpayne@69: #define SQLITE_TESTCTRL_FAULT_INSTALL 9 jpayne@69: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 jpayne@69: #define SQLITE_TESTCTRL_PENDING_BYTE 11 jpayne@69: #define SQLITE_TESTCTRL_ASSERT 12 jpayne@69: #define SQLITE_TESTCTRL_ALWAYS 13 jpayne@69: #define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ jpayne@69: #define SQLITE_TESTCTRL_JSON_SELFCHECK 14 jpayne@69: #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 jpayne@69: #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ jpayne@69: #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ jpayne@69: #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 jpayne@69: #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 jpayne@69: #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ jpayne@69: #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 jpayne@69: #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 jpayne@69: #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 jpayne@69: #define SQLITE_TESTCTRL_BYTEORDER 22 jpayne@69: #define SQLITE_TESTCTRL_ISINIT 23 jpayne@69: #define SQLITE_TESTCTRL_SORTER_MMAP 24 jpayne@69: #define SQLITE_TESTCTRL_IMPOSTER 25 jpayne@69: #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 jpayne@69: #define SQLITE_TESTCTRL_RESULT_INTREAL 27 jpayne@69: #define SQLITE_TESTCTRL_PRNG_SEED 28 jpayne@69: #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 jpayne@69: #define SQLITE_TESTCTRL_SEEK_COUNT 30 jpayne@69: #define SQLITE_TESTCTRL_TRACEFLAGS 31 jpayne@69: #define SQLITE_TESTCTRL_TUNE 32 jpayne@69: #define SQLITE_TESTCTRL_LOGEST 33 jpayne@69: #define SQLITE_TESTCTRL_USELONGDOUBLE 34 jpayne@69: #define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: SQL Keyword Checking jpayne@69: ** jpayne@69: ** These routines provide access to the set of SQL language keywords jpayne@69: ** recognized by SQLite. Applications can uses these routines to determine jpayne@69: ** whether or not a specific identifier needs to be escaped (for example, jpayne@69: ** by enclosing in double-quotes) so as not to confuse the parser. jpayne@69: ** jpayne@69: ** The sqlite3_keyword_count() interface returns the number of distinct jpayne@69: ** keywords understood by SQLite. jpayne@69: ** jpayne@69: ** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and jpayne@69: ** makes *Z point to that keyword expressed as UTF8 and writes the number jpayne@69: ** of bytes in the keyword into *L. The string that *Z points to is not jpayne@69: ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns jpayne@69: ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z jpayne@69: ** or L are NULL or invalid pointers then calls to jpayne@69: ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. jpayne@69: ** jpayne@69: ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not jpayne@69: ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero jpayne@69: ** if it is and zero if not. jpayne@69: ** jpayne@69: ** The parser used by SQLite is forgiving. It is often possible to use jpayne@69: ** a keyword as an identifier as long as such use does not result in a jpayne@69: ** parsing ambiguity. For example, the statement jpayne@69: ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and jpayne@69: ** creates a new table named "BEGIN" with three columns named jpayne@69: ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid jpayne@69: ** using keywords as identifiers. Common techniques used to avoid keyword jpayne@69: ** name collisions include: jpayne@69: ** jpayne@69: ** jpayne@69: ** Note that the number of keywords understood by SQLite can depend on jpayne@69: ** compile-time options. For example, "VACUUM" is not a keyword if jpayne@69: ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, jpayne@69: ** new keywords may be added to future releases of SQLite. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_keyword_count(void); jpayne@69: SQLITE_API int sqlite3_keyword_name(int,const char**,int*); jpayne@69: SQLITE_API int sqlite3_keyword_check(const char*,int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Dynamic String Object jpayne@69: ** KEYWORDS: {dynamic string} jpayne@69: ** jpayne@69: ** An instance of the sqlite3_str object contains a dynamically-sized jpayne@69: ** string under construction. jpayne@69: ** jpayne@69: ** The lifecycle of an sqlite3_str object is as follows: jpayne@69: **
    jpayne@69: **
  1. ^The sqlite3_str object is created using [sqlite3_str_new()]. jpayne@69: **
  2. ^Text is appended to the sqlite3_str object using various jpayne@69: ** methods, such as [sqlite3_str_appendf()]. jpayne@69: **
  3. ^The sqlite3_str object is destroyed and the string it created jpayne@69: ** is returned using the [sqlite3_str_finish()] interface. jpayne@69: **
jpayne@69: */ jpayne@69: typedef struct sqlite3_str sqlite3_str; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create A New Dynamic String Object jpayne@69: ** CONSTRUCTOR: sqlite3_str jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_new(D)] interface allocates and initializes jpayne@69: ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by jpayne@69: ** [sqlite3_str_new()] must be freed by a subsequent call to jpayne@69: ** [sqlite3_str_finish(X)]. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a jpayne@69: ** valid [sqlite3_str] object, though in the event of an out-of-memory jpayne@69: ** error the returned object might be a special singleton that will jpayne@69: ** silently reject new text, always return SQLITE_NOMEM from jpayne@69: ** [sqlite3_str_errcode()], always return 0 for jpayne@69: ** [sqlite3_str_length()], and always return NULL from jpayne@69: ** [sqlite3_str_finish(X)]. It is always safe to use the value jpayne@69: ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter jpayne@69: ** to any of the other [sqlite3_str] methods. jpayne@69: ** jpayne@69: ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the jpayne@69: ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum jpayne@69: ** length of the string contained in the [sqlite3_str] object will be jpayne@69: ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead jpayne@69: ** of [SQLITE_MAX_LENGTH]. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Finalize A Dynamic String jpayne@69: ** DESTRUCTOR: sqlite3_str jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X jpayne@69: ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] jpayne@69: ** that contains the constructed string. The calling application should jpayne@69: ** pass the returned value to [sqlite3_free()] to avoid a memory leak. jpayne@69: ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any jpayne@69: ** errors were encountered during construction of the string. ^The jpayne@69: ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the jpayne@69: ** string in [sqlite3_str] object X is zero bytes long. jpayne@69: */ jpayne@69: SQLITE_API char *sqlite3_str_finish(sqlite3_str*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Add Content To A Dynamic String jpayne@69: ** METHOD: sqlite3_str jpayne@69: ** jpayne@69: ** These interfaces add content to an sqlite3_str object previously obtained jpayne@69: ** from [sqlite3_str_new()]. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_appendf(X,F,...)] and jpayne@69: ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] jpayne@69: ** functionality of SQLite to append formatted text onto the end of jpayne@69: ** [sqlite3_str] object X. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S jpayne@69: ** onto the end of the [sqlite3_str] object X. N must be non-negative. jpayne@69: ** S must contain at least N non-zero bytes of content. To append a jpayne@69: ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] jpayne@69: ** method instead. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of jpayne@69: ** zero-terminated string S onto the end of [sqlite3_str] object X. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the jpayne@69: ** single-byte character C onto the end of [sqlite3_str] object X. jpayne@69: ** ^This method can be used, for example, to add whitespace indentation. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_reset(X)] method resets the string under construction jpayne@69: ** inside [sqlite3_str] object X back to zero bytes in length. jpayne@69: ** jpayne@69: ** These methods do not return a result code. ^If an error occurs, that fact jpayne@69: ** is recorded in the [sqlite3_str] object and can be recovered by a jpayne@69: ** subsequent call to [sqlite3_str_errcode(X)]. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); jpayne@69: SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); jpayne@69: SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); jpayne@69: SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); jpayne@69: SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); jpayne@69: SQLITE_API void sqlite3_str_reset(sqlite3_str*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Status Of A Dynamic String jpayne@69: ** METHOD: sqlite3_str jpayne@69: ** jpayne@69: ** These interfaces return the current status of an [sqlite3_str] object. jpayne@69: ** jpayne@69: ** ^If any prior errors have occurred while constructing the dynamic string jpayne@69: ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return jpayne@69: ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns jpayne@69: ** [SQLITE_NOMEM] following any out-of-memory error, or jpayne@69: ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds jpayne@69: ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, jpayne@69: ** of the dynamic string under construction in [sqlite3_str] object X. jpayne@69: ** ^The length returned by [sqlite3_str_length(X)] does not include the jpayne@69: ** zero-termination byte. jpayne@69: ** jpayne@69: ** ^The [sqlite3_str_value(X)] method returns a pointer to the current jpayne@69: ** content of the dynamic string under construction in X. The value jpayne@69: ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X jpayne@69: ** and might be freed or altered by any subsequent method on the same jpayne@69: ** [sqlite3_str] object. Applications must not used the pointer returned jpayne@69: ** [sqlite3_str_value(X)] after any subsequent method call on the same jpayne@69: ** object. ^Applications may change the content of the string returned jpayne@69: ** by [sqlite3_str_value(X)] as long as they do not write into any bytes jpayne@69: ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or jpayne@69: ** write any byte after any subsequent sqlite3_str method call. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_str_errcode(sqlite3_str*); jpayne@69: SQLITE_API int sqlite3_str_length(sqlite3_str*); jpayne@69: SQLITE_API char *sqlite3_str_value(sqlite3_str*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: SQLite Runtime Status jpayne@69: ** jpayne@69: ** ^These interfaces are used to retrieve runtime status information jpayne@69: ** about the performance of SQLite, and optionally to reset various jpayne@69: ** highwater marks. ^The first argument is an integer code for jpayne@69: ** the specific parameter to measure. ^(Recognized integer codes jpayne@69: ** are of the form [status parameters | SQLITE_STATUS_...].)^ jpayne@69: ** ^The current value of the parameter is returned into *pCurrent. jpayne@69: ** ^The highest recorded value is returned in *pHighwater. ^If the jpayne@69: ** resetFlag is true, then the highest record value is reset after jpayne@69: ** *pHighwater is written. ^(Some parameters do not record the highest jpayne@69: ** value. For those parameters jpayne@69: ** nothing is written into *pHighwater and the resetFlag is ignored.)^ jpayne@69: ** ^(Other parameters record only the highwater mark and not the current jpayne@69: ** value. For these latter parameters nothing is written into *pCurrent.)^ jpayne@69: ** jpayne@69: ** ^The sqlite3_status() and sqlite3_status64() routines return jpayne@69: ** SQLITE_OK on success and a non-zero [error code] on failure. jpayne@69: ** jpayne@69: ** If either the current value or the highwater mark is too large to jpayne@69: ** be represented by a 32-bit integer, then the values returned by jpayne@69: ** sqlite3_status() are undefined. jpayne@69: ** jpayne@69: ** See also: [sqlite3_db_status()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); jpayne@69: SQLITE_API int sqlite3_status64( jpayne@69: int op, jpayne@69: sqlite3_int64 *pCurrent, jpayne@69: sqlite3_int64 *pHighwater, jpayne@69: int resetFlag jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Status Parameters jpayne@69: ** KEYWORDS: {status parameters} jpayne@69: ** jpayne@69: ** These integer constants designate various run-time status parameters jpayne@69: ** that can be returned by [sqlite3_status()]. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_STATUS_MEMORY_USED]] ^(
SQLITE_STATUS_MEMORY_USED
jpayne@69: **
This parameter is the current amount of memory checked out jpayne@69: ** using [sqlite3_malloc()], either directly or indirectly. The jpayne@69: ** figure includes calls made to [sqlite3_malloc()] by the application jpayne@69: ** and internal memory usage by the SQLite library. Auxiliary page-cache jpayne@69: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in jpayne@69: ** this parameter. The amount returned is the sum of the allocation jpayne@69: ** sizes as reported by the xSize method in [sqlite3_mem_methods].
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(
SQLITE_STATUS_MALLOC_SIZE
jpayne@69: **
This parameter records the largest memory allocation request jpayne@69: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their jpayne@69: ** internal equivalents). Only the value returned in the jpayne@69: ** *pHighwater parameter to [sqlite3_status()] is of interest. jpayne@69: ** The value written into the *pCurrent parameter is undefined.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(
SQLITE_STATUS_MALLOC_COUNT
jpayne@69: **
This parameter records the number of separate memory allocations jpayne@69: ** currently checked out.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(
SQLITE_STATUS_PAGECACHE_USED
jpayne@69: **
This parameter returns the number of pages used out of the jpayne@69: ** [pagecache memory allocator] that was configured using jpayne@69: ** [SQLITE_CONFIG_PAGECACHE]. The jpayne@69: ** value returned is in pages, not in bytes.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] jpayne@69: ** ^(
SQLITE_STATUS_PAGECACHE_OVERFLOW
jpayne@69: **
This parameter returns the number of bytes of page cache jpayne@69: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] jpayne@69: ** buffer and where forced to overflow to [sqlite3_malloc()]. The jpayne@69: ** returned value includes allocations that overflowed because they jpayne@69: ** where too large (they were larger than the "sz" parameter to jpayne@69: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because jpayne@69: ** no space was left in the page cache.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(
SQLITE_STATUS_PAGECACHE_SIZE
jpayne@69: **
This parameter records the largest memory allocation request jpayne@69: ** handed to the [pagecache memory allocator]. Only the value returned in the jpayne@69: ** *pHighwater parameter to [sqlite3_status()] is of interest. jpayne@69: ** The value written into the *pCurrent parameter is undefined.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_SCRATCH_USED]]
SQLITE_STATUS_SCRATCH_USED
jpayne@69: **
No longer used.
jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(
SQLITE_STATUS_SCRATCH_OVERFLOW
jpayne@69: **
No longer used.
jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_SCRATCH_SIZE]]
SQLITE_STATUS_SCRATCH_SIZE
jpayne@69: **
No longer used.
jpayne@69: ** jpayne@69: ** [[SQLITE_STATUS_PARSER_STACK]] ^(
SQLITE_STATUS_PARSER_STACK
jpayne@69: **
The *pHighwater parameter records the deepest parser stack. jpayne@69: ** The *pCurrent value is undefined. The *pHighwater value is only jpayne@69: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].
)^ jpayne@69: **
jpayne@69: ** jpayne@69: ** New status parameters may be added from time to time. jpayne@69: */ jpayne@69: #define SQLITE_STATUS_MEMORY_USED 0 jpayne@69: #define SQLITE_STATUS_PAGECACHE_USED 1 jpayne@69: #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 jpayne@69: #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ jpayne@69: #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ jpayne@69: #define SQLITE_STATUS_MALLOC_SIZE 5 jpayne@69: #define SQLITE_STATUS_PARSER_STACK 6 jpayne@69: #define SQLITE_STATUS_PAGECACHE_SIZE 7 jpayne@69: #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ jpayne@69: #define SQLITE_STATUS_MALLOC_COUNT 9 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Connection Status jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^This interface is used to retrieve runtime status information jpayne@69: ** about a single [database connection]. ^The first argument is the jpayne@69: ** database connection object to be interrogated. ^The second argument jpayne@69: ** is an integer constant, taken from the set of jpayne@69: ** [SQLITE_DBSTATUS options], that jpayne@69: ** determines the parameter to interrogate. The set of jpayne@69: ** [SQLITE_DBSTATUS options] is likely jpayne@69: ** to grow in future releases of SQLite. jpayne@69: ** jpayne@69: ** ^The current value of the requested parameter is written into *pCur jpayne@69: ** and the highest instantaneous value is written into *pHiwtr. ^If jpayne@69: ** the resetFlg is true, then the highest instantaneous value is jpayne@69: ** reset back down to the current value. jpayne@69: ** jpayne@69: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a jpayne@69: ** non-zero [error code] on failure. jpayne@69: ** jpayne@69: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Status Parameters for database connections jpayne@69: ** KEYWORDS: {SQLITE_DBSTATUS options} jpayne@69: ** jpayne@69: ** These constants are the available integer "verbs" that can be passed as jpayne@69: ** the second argument to the [sqlite3_db_status()] interface. jpayne@69: ** jpayne@69: ** New verbs may be added in future releases of SQLite. Existing verbs jpayne@69: ** might be discontinued. Applications should check the return code from jpayne@69: ** [sqlite3_db_status()] to make sure that the call worked. jpayne@69: ** The [sqlite3_db_status()] interface will return a non-zero error code jpayne@69: ** if a discontinued or unsupported verb is invoked. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(
SQLITE_DBSTATUS_LOOKASIDE_USED
jpayne@69: **
This parameter returns the number of lookaside memory slots currently jpayne@69: ** checked out.
)^ jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(
SQLITE_DBSTATUS_LOOKASIDE_HIT
jpayne@69: **
This parameter returns the number of malloc attempts that were jpayne@69: ** satisfied using lookaside memory. Only the high-water value is meaningful; jpayne@69: ** the current value is always zero.)^ jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] jpayne@69: ** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
jpayne@69: **
This parameter returns the number malloc attempts that might have jpayne@69: ** been satisfied using lookaside memory but failed due to the amount of jpayne@69: ** memory requested being larger than the lookaside slot size. jpayne@69: ** Only the high-water value is meaningful; jpayne@69: ** the current value is always zero.)^ jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] jpayne@69: ** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
jpayne@69: **
This parameter returns the number malloc attempts that might have jpayne@69: ** been satisfied using lookaside memory but failed due to all lookaside jpayne@69: ** memory already being in use. jpayne@69: ** Only the high-water value is meaningful; jpayne@69: ** the current value is always zero.)^ jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(
SQLITE_DBSTATUS_CACHE_USED
jpayne@69: **
This parameter returns the approximate number of bytes of heap jpayne@69: ** memory used by all pager caches associated with the database connection.)^ jpayne@69: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] jpayne@69: ** ^(
SQLITE_DBSTATUS_CACHE_USED_SHARED
jpayne@69: **
This parameter is similar to DBSTATUS_CACHE_USED, except that if a jpayne@69: ** pager cache is shared between two or more connections the bytes of heap jpayne@69: ** memory used by that pager cache is divided evenly between the attached jpayne@69: ** connections.)^ In other words, if none of the pager caches associated jpayne@69: ** with the database connection are shared, this request returns the same jpayne@69: ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are jpayne@69: ** shared, the value returned by this call will be smaller than that returned jpayne@69: ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with jpayne@69: ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(
SQLITE_DBSTATUS_SCHEMA_USED
jpayne@69: **
This parameter returns the approximate number of bytes of heap jpayne@69: ** memory used to store the schema for all databases associated jpayne@69: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ jpayne@69: ** ^The full amount of memory used by the schemas is reported, even if the jpayne@69: ** schema memory is shared with other database connections due to jpayne@69: ** [shared cache mode] being enabled. jpayne@69: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(
SQLITE_DBSTATUS_STMT_USED
jpayne@69: **
This parameter returns the approximate number of bytes of heap jpayne@69: ** and lookaside memory used by all prepared statements associated with jpayne@69: ** the database connection.)^ jpayne@69: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(
SQLITE_DBSTATUS_CACHE_HIT
jpayne@69: **
This parameter returns the number of pager cache hits that have jpayne@69: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT jpayne@69: ** is always 0. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(
SQLITE_DBSTATUS_CACHE_MISS
jpayne@69: **
This parameter returns the number of pager cache misses that have jpayne@69: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS jpayne@69: ** is always 0. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(
SQLITE_DBSTATUS_CACHE_WRITE
jpayne@69: **
This parameter returns the number of dirty cache entries that have jpayne@69: ** been written to disk. Specifically, the number of pages written to the jpayne@69: ** wal file in wal mode databases, or the number of pages written to the jpayne@69: ** database file in rollback mode databases. Any pages written as part of jpayne@69: ** transaction rollback or database recovery operations are not included. jpayne@69: ** If an IO or other error occurs while writing a page to disk, the effect jpayne@69: ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The jpayne@69: ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(
SQLITE_DBSTATUS_CACHE_SPILL
jpayne@69: **
This parameter returns the number of dirty cache entries that have jpayne@69: ** been written to disk in the middle of a transaction due to the page jpayne@69: ** cache overflowing. Transactions are more efficient if they are written jpayne@69: ** to disk all at once. When pages spill mid-transaction, that introduces jpayne@69: ** additional overhead. This parameter can be used help identify jpayne@69: ** inefficiencies that can be resolved by increasing the cache size. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(
SQLITE_DBSTATUS_DEFERRED_FKS
jpayne@69: **
This parameter returns zero for the current value if and only if jpayne@69: ** all foreign key constraints (deferred or immediate) have been jpayne@69: ** resolved.)^ ^The highwater mark is always 0. jpayne@69: **
jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 jpayne@69: #define SQLITE_DBSTATUS_CACHE_USED 1 jpayne@69: #define SQLITE_DBSTATUS_SCHEMA_USED 2 jpayne@69: #define SQLITE_DBSTATUS_STMT_USED 3 jpayne@69: #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 jpayne@69: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 jpayne@69: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 jpayne@69: #define SQLITE_DBSTATUS_CACHE_HIT 7 jpayne@69: #define SQLITE_DBSTATUS_CACHE_MISS 8 jpayne@69: #define SQLITE_DBSTATUS_CACHE_WRITE 9 jpayne@69: #define SQLITE_DBSTATUS_DEFERRED_FKS 10 jpayne@69: #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 jpayne@69: #define SQLITE_DBSTATUS_CACHE_SPILL 12 jpayne@69: #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepared Statement Status jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^(Each prepared statement maintains various jpayne@69: ** [SQLITE_STMTSTATUS counters] that measure the number jpayne@69: ** of times it has performed specific operations.)^ These counters can jpayne@69: ** be used to monitor the performance characteristics of the prepared jpayne@69: ** statements. For example, if the number of table steps greatly exceeds jpayne@69: ** the number of table searches or result rows, that would tend to indicate jpayne@69: ** that the prepared statement is using a full table scan rather than jpayne@69: ** an index. jpayne@69: ** jpayne@69: ** ^(This interface is used to retrieve and reset counter values from jpayne@69: ** a [prepared statement]. The first argument is the prepared statement jpayne@69: ** object to be interrogated. The second argument jpayne@69: ** is an integer code for a specific [SQLITE_STMTSTATUS counter] jpayne@69: ** to be interrogated.)^ jpayne@69: ** ^The current value of the requested counter is returned. jpayne@69: ** ^If the resetFlg is true, then the counter is reset to zero after this jpayne@69: ** interface call returns. jpayne@69: ** jpayne@69: ** See also: [sqlite3_status()] and [sqlite3_db_status()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Status Parameters for prepared statements jpayne@69: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} jpayne@69: ** jpayne@69: ** These preprocessor macros define integer codes that name counter jpayne@69: ** values associated with the [sqlite3_stmt_status()] interface. jpayne@69: ** The meanings of the various counters are as follows: jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]]
SQLITE_STMTSTATUS_FULLSCAN_STEP
jpayne@69: **
^This is the number of times that SQLite has stepped forward in jpayne@69: ** a table as part of a full table scan. Large numbers for this counter jpayne@69: ** may indicate opportunities for performance improvement through jpayne@69: ** careful use of indices.
jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_SORT]]
SQLITE_STMTSTATUS_SORT
jpayne@69: **
^This is the number of sort operations that have occurred. jpayne@69: ** A non-zero value in this counter may indicate an opportunity to jpayne@69: ** improvement performance through careful use of indices.
jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_AUTOINDEX]]
SQLITE_STMTSTATUS_AUTOINDEX
jpayne@69: **
^This is the number of rows inserted into transient indices that jpayne@69: ** were created automatically in order to help joins run faster. jpayne@69: ** A non-zero value in this counter may indicate an opportunity to jpayne@69: ** improvement performance by adding permanent indices that do not jpayne@69: ** need to be reinitialized each time the statement is run.
jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_VM_STEP]]
SQLITE_STMTSTATUS_VM_STEP
jpayne@69: **
^This is the number of virtual machine operations executed jpayne@69: ** by the prepared statement if that number is less than or equal jpayne@69: ** to 2147483647. The number of virtual machine operations can be jpayne@69: ** used as a proxy for the total work done by the prepared statement. jpayne@69: ** If the number of virtual machine operations exceeds 2147483647 jpayne@69: ** then the value returned by this statement status code is undefined. jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_REPREPARE]]
SQLITE_STMTSTATUS_REPREPARE
jpayne@69: **
^This is the number of times that the prepare statement has been jpayne@69: ** automatically regenerated due to schema changes or changes to jpayne@69: ** [bound parameters] that might affect the query plan. jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_RUN]]
SQLITE_STMTSTATUS_RUN
jpayne@69: **
^This is the number of times that the prepared statement has jpayne@69: ** been run. A single "run" for the purposes of this counter is one jpayne@69: ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. jpayne@69: ** The counter is incremented on the first [sqlite3_step()] call of each jpayne@69: ** cycle. jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_FILTER_MISS]] jpayne@69: ** [[SQLITE_STMTSTATUS_FILTER HIT]] jpayne@69: **
SQLITE_STMTSTATUS_FILTER_HIT
jpayne@69: ** SQLITE_STMTSTATUS_FILTER_MISS
jpayne@69: **
^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join jpayne@69: ** step was bypassed because a Bloom filter returned not-found. The jpayne@69: ** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of jpayne@69: ** times that the Bloom filter returned a find, and thus the join step jpayne@69: ** had to be processed as normal. jpayne@69: ** jpayne@69: ** [[SQLITE_STMTSTATUS_MEMUSED]]
SQLITE_STMTSTATUS_MEMUSED
jpayne@69: **
^This is the approximate number of bytes of heap memory jpayne@69: ** used to store the prepared statement. ^This value is not actually jpayne@69: ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() jpayne@69: ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. jpayne@69: **
jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 jpayne@69: #define SQLITE_STMTSTATUS_SORT 2 jpayne@69: #define SQLITE_STMTSTATUS_AUTOINDEX 3 jpayne@69: #define SQLITE_STMTSTATUS_VM_STEP 4 jpayne@69: #define SQLITE_STMTSTATUS_REPREPARE 5 jpayne@69: #define SQLITE_STMTSTATUS_RUN 6 jpayne@69: #define SQLITE_STMTSTATUS_FILTER_MISS 7 jpayne@69: #define SQLITE_STMTSTATUS_FILTER_HIT 8 jpayne@69: #define SQLITE_STMTSTATUS_MEMUSED 99 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Custom Page Cache Object jpayne@69: ** jpayne@69: ** The sqlite3_pcache type is opaque. It is implemented by jpayne@69: ** the pluggable module. The SQLite core has no knowledge of jpayne@69: ** its size or internal structure and never deals with the jpayne@69: ** sqlite3_pcache object except by holding and passing pointers jpayne@69: ** to the object. jpayne@69: ** jpayne@69: ** See [sqlite3_pcache_methods2] for additional information. jpayne@69: */ jpayne@69: typedef struct sqlite3_pcache sqlite3_pcache; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Custom Page Cache Object jpayne@69: ** jpayne@69: ** The sqlite3_pcache_page object represents a single page in the jpayne@69: ** page cache. The page cache will allocate instances of this jpayne@69: ** object. Various methods of the page cache use pointers to instances jpayne@69: ** of this object as parameters or as their return value. jpayne@69: ** jpayne@69: ** See [sqlite3_pcache_methods2] for additional information. jpayne@69: */ jpayne@69: typedef struct sqlite3_pcache_page sqlite3_pcache_page; jpayne@69: struct sqlite3_pcache_page { jpayne@69: void *pBuf; /* The content of the page */ jpayne@69: void *pExtra; /* Extra information associated with the page */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Application Defined Page Cache. jpayne@69: ** KEYWORDS: {page cache} jpayne@69: ** jpayne@69: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can jpayne@69: ** register an alternative page cache implementation by passing in an jpayne@69: ** instance of the sqlite3_pcache_methods2 structure.)^ jpayne@69: ** In many applications, most of the heap memory allocated by jpayne@69: ** SQLite is used for the page cache. jpayne@69: ** By implementing a jpayne@69: ** custom page cache using this API, an application can better control jpayne@69: ** the amount of memory consumed by SQLite, the way in which jpayne@69: ** that memory is allocated and released, and the policies used to jpayne@69: ** determine exactly which parts of a database file are cached and for jpayne@69: ** how long. jpayne@69: ** jpayne@69: ** The alternative page cache mechanism is an jpayne@69: ** extreme measure that is only needed by the most demanding applications. jpayne@69: ** The built-in page cache is recommended for most uses. jpayne@69: ** jpayne@69: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an jpayne@69: ** internal buffer by SQLite within the call to [sqlite3_config]. Hence jpayne@69: ** the application may discard the parameter after the call to jpayne@69: ** [sqlite3_config()] returns.)^ jpayne@69: ** jpayne@69: ** [[the xInit() page cache method]] jpayne@69: ** ^(The xInit() method is called once for each effective jpayne@69: ** call to [sqlite3_initialize()])^ jpayne@69: ** (usually only once during the lifetime of the process). ^(The xInit() jpayne@69: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ jpayne@69: ** The intent of the xInit() method is to set up global data structures jpayne@69: ** required by the custom page cache implementation. jpayne@69: ** ^(If the xInit() method is NULL, then the jpayne@69: ** built-in default page cache is used instead of the application defined jpayne@69: ** page cache.)^ jpayne@69: ** jpayne@69: ** [[the xShutdown() page cache method]] jpayne@69: ** ^The xShutdown() method is called by [sqlite3_shutdown()]. jpayne@69: ** It can be used to clean up jpayne@69: ** any outstanding resources before process shutdown, if required. jpayne@69: ** ^The xShutdown() method may be NULL. jpayne@69: ** jpayne@69: ** ^SQLite automatically serializes calls to the xInit method, jpayne@69: ** so the xInit method need not be threadsafe. ^The jpayne@69: ** xShutdown method is only called from [sqlite3_shutdown()] so it does jpayne@69: ** not need to be threadsafe either. All other methods must be threadsafe jpayne@69: ** in multithreaded applications. jpayne@69: ** jpayne@69: ** ^SQLite will never invoke xInit() more than once without an intervening jpayne@69: ** call to xShutdown(). jpayne@69: ** jpayne@69: ** [[the xCreate() page cache methods]] jpayne@69: ** ^SQLite invokes the xCreate() method to construct a new cache instance. jpayne@69: ** SQLite will typically create one cache instance for each open database file, jpayne@69: ** though this is not guaranteed. ^The jpayne@69: ** first parameter, szPage, is the size in bytes of the pages that must jpayne@69: ** be allocated by the cache. ^szPage will always a power of two. ^The jpayne@69: ** second parameter szExtra is a number of bytes of extra storage jpayne@69: ** associated with each page cache entry. ^The szExtra parameter will jpayne@69: ** a number less than 250. SQLite will use the jpayne@69: ** extra szExtra bytes on each page to store metadata about the underlying jpayne@69: ** database page on disk. The value passed into szExtra depends jpayne@69: ** on the SQLite version, the target platform, and how SQLite was compiled. jpayne@69: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being jpayne@69: ** created will be used to cache database pages of a file stored on disk, or jpayne@69: ** false if it is used for an in-memory database. The cache implementation jpayne@69: ** does not have to do anything special based with the value of bPurgeable; jpayne@69: ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will jpayne@69: ** never invoke xUnpin() except to deliberately delete a page. jpayne@69: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to jpayne@69: ** false will always have the "discard" flag set to true. jpayne@69: ** ^Hence, a cache created with bPurgeable false will jpayne@69: ** never contain any unpinned pages. jpayne@69: ** jpayne@69: ** [[the xCachesize() page cache method]] jpayne@69: ** ^(The xCachesize() method may be called at any time by SQLite to set the jpayne@69: ** suggested maximum cache-size (number of pages stored by) the cache jpayne@69: ** instance passed as the first argument. This is the value configured using jpayne@69: ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable jpayne@69: ** parameter, the implementation is not required to do anything with this jpayne@69: ** value; it is advisory only. jpayne@69: ** jpayne@69: ** [[the xPagecount() page cache methods]] jpayne@69: ** The xPagecount() method must return the number of pages currently jpayne@69: ** stored in the cache, both pinned and unpinned. jpayne@69: ** jpayne@69: ** [[the xFetch() page cache methods]] jpayne@69: ** The xFetch() method locates a page in the cache and returns a pointer to jpayne@69: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. jpayne@69: ** The pBuf element of the returned sqlite3_pcache_page object will be a jpayne@69: ** pointer to a buffer of szPage bytes used to store the content of a jpayne@69: ** single database page. The pExtra element of sqlite3_pcache_page will be jpayne@69: ** a pointer to the szExtra bytes of extra storage that SQLite has requested jpayne@69: ** for each entry in the page cache. jpayne@69: ** jpayne@69: ** The page to be fetched is determined by the key. ^The minimum key value jpayne@69: ** is 1. After it has been retrieved using xFetch, the page is considered jpayne@69: ** to be "pinned". jpayne@69: ** jpayne@69: ** If the requested page is already in the page cache, then the page cache jpayne@69: ** implementation must return a pointer to the page buffer with its content jpayne@69: ** intact. If the requested page is not already in the cache, then the jpayne@69: ** cache implementation should use the value of the createFlag jpayne@69: ** parameter to help it determined what action to take: jpayne@69: ** jpayne@69: ** jpayne@69: **
createFlag Behavior when page is not already in cache jpayne@69: **
0 Do not allocate a new page. Return NULL. jpayne@69: **
1 Allocate a new page if it easy and convenient to do so. jpayne@69: ** Otherwise return NULL. jpayne@69: **
2 Make every effort to allocate a new page. Only return jpayne@69: ** NULL if allocating a new page is effectively impossible. jpayne@69: **
jpayne@69: ** jpayne@69: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite jpayne@69: ** will only use a createFlag of 2 after a prior call with a createFlag of 1 jpayne@69: ** failed.)^ In between the xFetch() calls, SQLite may jpayne@69: ** attempt to unpin one or more cache pages by spilling the content of jpayne@69: ** pinned pages to disk and synching the operating system disk cache. jpayne@69: ** jpayne@69: ** [[the xUnpin() page cache method]] jpayne@69: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page jpayne@69: ** as its second argument. If the third parameter, discard, is non-zero, jpayne@69: ** then the page must be evicted from the cache. jpayne@69: ** ^If the discard parameter is jpayne@69: ** zero, then the page may be discarded or retained at the discretion of jpayne@69: ** page cache implementation. ^The page cache implementation jpayne@69: ** may choose to evict unpinned pages at any time. jpayne@69: ** jpayne@69: ** The cache must not perform any reference counting. A single jpayne@69: ** call to xUnpin() unpins the page regardless of the number of prior calls jpayne@69: ** to xFetch(). jpayne@69: ** jpayne@69: ** [[the xRekey() page cache methods]] jpayne@69: ** The xRekey() method is used to change the key value associated with the jpayne@69: ** page passed as the second argument. If the cache jpayne@69: ** previously contains an entry associated with newKey, it must be jpayne@69: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not jpayne@69: ** to be pinned. jpayne@69: ** jpayne@69: ** When SQLite calls the xTruncate() method, the cache must discard all jpayne@69: ** existing cache entries with page numbers (keys) greater than or equal jpayne@69: ** to the value of the iLimit parameter passed to xTruncate(). If any jpayne@69: ** of these pages are pinned, they are implicitly unpinned, meaning that jpayne@69: ** they can be safely discarded. jpayne@69: ** jpayne@69: ** [[the xDestroy() page cache method]] jpayne@69: ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). jpayne@69: ** All resources associated with the specified cache should be freed. ^After jpayne@69: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] jpayne@69: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 jpayne@69: ** functions. jpayne@69: ** jpayne@69: ** [[the xShrink() page cache method]] jpayne@69: ** ^SQLite invokes the xShrink() method when it wants the page cache to jpayne@69: ** free up as much of heap memory as possible. The page cache implementation jpayne@69: ** is not obligated to free any memory, but well-behaved implementations should jpayne@69: ** do their best. jpayne@69: */ jpayne@69: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; jpayne@69: struct sqlite3_pcache_methods2 { jpayne@69: int iVersion; jpayne@69: void *pArg; jpayne@69: int (*xInit)(void*); jpayne@69: void (*xShutdown)(void*); jpayne@69: sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); jpayne@69: void (*xCachesize)(sqlite3_pcache*, int nCachesize); jpayne@69: int (*xPagecount)(sqlite3_pcache*); jpayne@69: sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); jpayne@69: void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); jpayne@69: void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, jpayne@69: unsigned oldKey, unsigned newKey); jpayne@69: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); jpayne@69: void (*xDestroy)(sqlite3_pcache*); jpayne@69: void (*xShrink)(sqlite3_pcache*); jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** This is the obsolete pcache_methods object that has now been replaced jpayne@69: ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is jpayne@69: ** retained in the header file for backwards compatibility only. jpayne@69: */ jpayne@69: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; jpayne@69: struct sqlite3_pcache_methods { jpayne@69: void *pArg; jpayne@69: int (*xInit)(void*); jpayne@69: void (*xShutdown)(void*); jpayne@69: sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); jpayne@69: void (*xCachesize)(sqlite3_pcache*, int nCachesize); jpayne@69: int (*xPagecount)(sqlite3_pcache*); jpayne@69: void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); jpayne@69: void (*xUnpin)(sqlite3_pcache*, void*, int discard); jpayne@69: void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); jpayne@69: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); jpayne@69: void (*xDestroy)(sqlite3_pcache*); jpayne@69: }; jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Online Backup Object jpayne@69: ** jpayne@69: ** The sqlite3_backup object records state information about an ongoing jpayne@69: ** online backup operation. ^The sqlite3_backup object is created by jpayne@69: ** a call to [sqlite3_backup_init()] and is destroyed by a call to jpayne@69: ** [sqlite3_backup_finish()]. jpayne@69: ** jpayne@69: ** See Also: [Using the SQLite Online Backup API] jpayne@69: */ jpayne@69: typedef struct sqlite3_backup sqlite3_backup; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Online Backup API. jpayne@69: ** jpayne@69: ** The backup API copies the content of one database into another. jpayne@69: ** It is useful either for creating backups of databases or jpayne@69: ** for copying in-memory databases to or from persistent files. jpayne@69: ** jpayne@69: ** See Also: [Using the SQLite Online Backup API] jpayne@69: ** jpayne@69: ** ^SQLite holds a write transaction open on the destination database file jpayne@69: ** for the duration of the backup operation. jpayne@69: ** ^The source database is read-locked only while it is being read; jpayne@69: ** it is not locked continuously for the entire backup operation. jpayne@69: ** ^Thus, the backup may be performed on a live source database without jpayne@69: ** preventing other database connections from jpayne@69: ** reading or writing to the source database while the backup is underway. jpayne@69: ** jpayne@69: ** ^(To perform a backup operation: jpayne@69: **
    jpayne@69: **
  1. sqlite3_backup_init() is called once to initialize the jpayne@69: ** backup, jpayne@69: **
  2. sqlite3_backup_step() is called one or more times to transfer jpayne@69: ** the data between the two databases, and finally jpayne@69: **
  3. sqlite3_backup_finish() is called to release all resources jpayne@69: ** associated with the backup operation. jpayne@69: **
)^ jpayne@69: ** There should be exactly one call to sqlite3_backup_finish() for each jpayne@69: ** successful call to sqlite3_backup_init(). jpayne@69: ** jpayne@69: ** [[sqlite3_backup_init()]] sqlite3_backup_init() jpayne@69: ** jpayne@69: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the jpayne@69: ** [database connection] associated with the destination database jpayne@69: ** and the database name, respectively. jpayne@69: ** ^The database name is "main" for the main database, "temp" for the jpayne@69: ** temporary database, or the name specified after the AS keyword in jpayne@69: ** an [ATTACH] statement for an attached database. jpayne@69: ** ^The S and M arguments passed to jpayne@69: ** sqlite3_backup_init(D,N,S,M) identify the [database connection] jpayne@69: ** and database name of the source database, respectively. jpayne@69: ** ^The source and destination [database connections] (parameters S and D) jpayne@69: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with jpayne@69: ** an error. jpayne@69: ** jpayne@69: ** ^A call to sqlite3_backup_init() will fail, returning NULL, if jpayne@69: ** there is already a read or read-write transaction open on the jpayne@69: ** destination database. jpayne@69: ** jpayne@69: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is jpayne@69: ** returned and an error code and error message are stored in the jpayne@69: ** destination [database connection] D. jpayne@69: ** ^The error code and message for the failed call to sqlite3_backup_init() jpayne@69: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or jpayne@69: ** [sqlite3_errmsg16()] functions. jpayne@69: ** ^A successful call to sqlite3_backup_init() returns a pointer to an jpayne@69: ** [sqlite3_backup] object. jpayne@69: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and jpayne@69: ** sqlite3_backup_finish() functions to perform the specified backup jpayne@69: ** operation. jpayne@69: ** jpayne@69: ** [[sqlite3_backup_step()]] sqlite3_backup_step() jpayne@69: ** jpayne@69: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between jpayne@69: ** the source and destination databases specified by [sqlite3_backup] object B. jpayne@69: ** ^If N is negative, all remaining source pages are copied. jpayne@69: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there jpayne@69: ** are still more pages to be copied, then the function returns [SQLITE_OK]. jpayne@69: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages jpayne@69: ** from source to destination, then it returns [SQLITE_DONE]. jpayne@69: ** ^If an error occurs while running sqlite3_backup_step(B,N), jpayne@69: ** then an [error code] is returned. ^As well as [SQLITE_OK] and jpayne@69: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], jpayne@69: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an jpayne@69: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. jpayne@69: ** jpayne@69: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if jpayne@69: **
    jpayne@69: **
  1. the destination database was opened read-only, or jpayne@69: **
  2. the destination database is using write-ahead-log journaling jpayne@69: ** and the destination and source page sizes differ, or jpayne@69: **
  3. the destination database is an in-memory database and the jpayne@69: ** destination and source page sizes differ. jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then jpayne@69: ** the [sqlite3_busy_handler | busy-handler function] jpayne@69: ** is invoked (if one is specified). ^If the jpayne@69: ** busy-handler returns non-zero before the lock is available, then jpayne@69: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to jpayne@69: ** sqlite3_backup_step() can be retried later. ^If the source jpayne@69: ** [database connection] jpayne@69: ** is being used to write to the source database when sqlite3_backup_step() jpayne@69: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this jpayne@69: ** case the call to sqlite3_backup_step() can be retried later on. ^(If jpayne@69: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or jpayne@69: ** [SQLITE_READONLY] is returned, then jpayne@69: ** there is no point in retrying the call to sqlite3_backup_step(). These jpayne@69: ** errors are considered fatal.)^ The application must accept jpayne@69: ** that the backup operation has failed and pass the backup operation handle jpayne@69: ** to the sqlite3_backup_finish() to release associated resources. jpayne@69: ** jpayne@69: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock jpayne@69: ** on the destination file. ^The exclusive lock is not released until either jpayne@69: ** sqlite3_backup_finish() is called or the backup operation is complete jpayne@69: ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to jpayne@69: ** sqlite3_backup_step() obtains a [shared lock] on the source database that jpayne@69: ** lasts for the duration of the sqlite3_backup_step() call. jpayne@69: ** ^Because the source database is not locked between calls to jpayne@69: ** sqlite3_backup_step(), the source database may be modified mid-way jpayne@69: ** through the backup process. ^If the source database is modified by an jpayne@69: ** external process or via a database connection other than the one being jpayne@69: ** used by the backup operation, then the backup will be automatically jpayne@69: ** restarted by the next call to sqlite3_backup_step(). ^If the source jpayne@69: ** database is modified by the using the same database connection as is used jpayne@69: ** by the backup operation, then the backup database is automatically jpayne@69: ** updated at the same time. jpayne@69: ** jpayne@69: ** [[sqlite3_backup_finish()]] sqlite3_backup_finish() jpayne@69: ** jpayne@69: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the jpayne@69: ** application wishes to abandon the backup operation, the application jpayne@69: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). jpayne@69: ** ^The sqlite3_backup_finish() interfaces releases all jpayne@69: ** resources associated with the [sqlite3_backup] object. jpayne@69: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any jpayne@69: ** active write-transaction on the destination database is rolled back. jpayne@69: ** The [sqlite3_backup] object is invalid jpayne@69: ** and may not be used following a call to sqlite3_backup_finish(). jpayne@69: ** jpayne@69: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no jpayne@69: ** sqlite3_backup_step() errors occurred, regardless or whether or not jpayne@69: ** sqlite3_backup_step() completed. jpayne@69: ** ^If an out-of-memory condition or IO error occurred during any prior jpayne@69: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then jpayne@69: ** sqlite3_backup_finish() returns the corresponding [error code]. jpayne@69: ** jpayne@69: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() jpayne@69: ** is not a permanent error and does not affect the return value of jpayne@69: ** sqlite3_backup_finish(). jpayne@69: ** jpayne@69: ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] jpayne@69: ** sqlite3_backup_remaining() and sqlite3_backup_pagecount() jpayne@69: ** jpayne@69: ** ^The sqlite3_backup_remaining() routine returns the number of pages still jpayne@69: ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). jpayne@69: ** ^The sqlite3_backup_pagecount() routine returns the total number of pages jpayne@69: ** in the source database at the conclusion of the most recent jpayne@69: ** sqlite3_backup_step(). jpayne@69: ** ^(The values returned by these functions are only updated by jpayne@69: ** sqlite3_backup_step(). If the source database is modified in a way that jpayne@69: ** changes the size of the source database or the number of pages remaining, jpayne@69: ** those changes are not reflected in the output of sqlite3_backup_pagecount() jpayne@69: ** and sqlite3_backup_remaining() until after the next jpayne@69: ** sqlite3_backup_step().)^ jpayne@69: ** jpayne@69: ** Concurrent Usage of Database Handles jpayne@69: ** jpayne@69: ** ^The source [database connection] may be used by the application for other jpayne@69: ** purposes while a backup operation is underway or being initialized. jpayne@69: ** ^If SQLite is compiled and configured to support threadsafe database jpayne@69: ** connections, then the source database connection may be used concurrently jpayne@69: ** from within other threads. jpayne@69: ** jpayne@69: ** However, the application must guarantee that the destination jpayne@69: ** [database connection] is not passed to any other API (by any thread) after jpayne@69: ** sqlite3_backup_init() is called and before the corresponding call to jpayne@69: ** sqlite3_backup_finish(). SQLite does not currently check to see jpayne@69: ** if the application incorrectly accesses the destination [database connection] jpayne@69: ** and so no error code is reported, but the operations may malfunction jpayne@69: ** nevertheless. Use of the destination database connection while a jpayne@69: ** backup is in progress might also cause a mutex deadlock. jpayne@69: ** jpayne@69: ** If running in [shared cache mode], the application must jpayne@69: ** guarantee that the shared cache used by the destination database jpayne@69: ** is not accessed while the backup is running. In practice this means jpayne@69: ** that the application must guarantee that the disk file being jpayne@69: ** backed up to is not accessed by any connection within the process, jpayne@69: ** not just the specific connection that was passed to sqlite3_backup_init(). jpayne@69: ** jpayne@69: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple jpayne@69: ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). jpayne@69: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() jpayne@69: ** APIs are not strictly speaking threadsafe. If they are invoked at the jpayne@69: ** same time as another thread is invoking sqlite3_backup_step() it is jpayne@69: ** possible that they return invalid values. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_backup *sqlite3_backup_init( jpayne@69: sqlite3 *pDest, /* Destination database handle */ jpayne@69: const char *zDestName, /* Destination database name */ jpayne@69: sqlite3 *pSource, /* Source database handle */ jpayne@69: const char *zSourceName /* Source database name */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); jpayne@69: SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); jpayne@69: SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); jpayne@69: SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Unlock Notification jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^When running in shared-cache mode, a database operation may fail with jpayne@69: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or jpayne@69: ** individual tables within the shared-cache cannot be obtained. See jpayne@69: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. jpayne@69: ** ^This API may be used to register a callback that SQLite will invoke jpayne@69: ** when the connection currently holding the required lock relinquishes it. jpayne@69: ** ^This API is only available if the library was compiled with the jpayne@69: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. jpayne@69: ** jpayne@69: ** See Also: [Using the SQLite Unlock Notification Feature]. jpayne@69: ** jpayne@69: ** ^Shared-cache locks are released when a database connection concludes jpayne@69: ** its current transaction, either by committing it or rolling it back. jpayne@69: ** jpayne@69: ** ^When a connection (known as the blocked connection) fails to obtain a jpayne@69: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the jpayne@69: ** identity of the database connection (the blocking connection) that jpayne@69: ** has locked the required resource is stored internally. ^After an jpayne@69: ** application receives an SQLITE_LOCKED error, it may call the jpayne@69: ** sqlite3_unlock_notify() method with the blocked connection handle as jpayne@69: ** the first argument to register for a callback that will be invoked jpayne@69: ** when the blocking connections current transaction is concluded. ^The jpayne@69: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] jpayne@69: ** call that concludes the blocking connection's transaction. jpayne@69: ** jpayne@69: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, jpayne@69: ** there is a chance that the blocking connection will have already jpayne@69: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. jpayne@69: ** If this happens, then the specified callback is invoked immediately, jpayne@69: ** from within the call to sqlite3_unlock_notify().)^ jpayne@69: ** jpayne@69: ** ^If the blocked connection is attempting to obtain a write-lock on a jpayne@69: ** shared-cache table, and more than one other connection currently holds jpayne@69: ** a read-lock on the same table, then SQLite arbitrarily selects one of jpayne@69: ** the other connections to use as the blocking connection. jpayne@69: ** jpayne@69: ** ^(There may be at most one unlock-notify callback registered by a jpayne@69: ** blocked connection. If sqlite3_unlock_notify() is called when the jpayne@69: ** blocked connection already has a registered unlock-notify callback, jpayne@69: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is jpayne@69: ** called with a NULL pointer as its second argument, then any existing jpayne@69: ** unlock-notify callback is canceled. ^The blocked connections jpayne@69: ** unlock-notify callback may also be canceled by closing the blocked jpayne@69: ** connection using [sqlite3_close()]. jpayne@69: ** jpayne@69: ** The unlock-notify callback is not reentrant. If an application invokes jpayne@69: ** any sqlite3_xxx API functions from within an unlock-notify callback, a jpayne@69: ** crash or deadlock may be the result. jpayne@69: ** jpayne@69: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always jpayne@69: ** returns SQLITE_OK. jpayne@69: ** jpayne@69: ** Callback Invocation Details jpayne@69: ** jpayne@69: ** When an unlock-notify callback is registered, the application provides a jpayne@69: ** single void* pointer that is passed to the callback when it is invoked. jpayne@69: ** However, the signature of the callback function allows SQLite to pass jpayne@69: ** it an array of void* context pointers. The first argument passed to jpayne@69: ** an unlock-notify callback is a pointer to an array of void* pointers, jpayne@69: ** and the second is the number of entries in the array. jpayne@69: ** jpayne@69: ** When a blocking connection's transaction is concluded, there may be jpayne@69: ** more than one blocked connection that has registered for an unlock-notify jpayne@69: ** callback. ^If two or more such blocked connections have specified the jpayne@69: ** same callback function, then instead of invoking the callback function jpayne@69: ** multiple times, it is invoked once with the set of void* context pointers jpayne@69: ** specified by the blocked connections bundled together into an array. jpayne@69: ** This gives the application an opportunity to prioritize any actions jpayne@69: ** related to the set of unblocked database connections. jpayne@69: ** jpayne@69: ** Deadlock Detection jpayne@69: ** jpayne@69: ** Assuming that after registering for an unlock-notify callback a jpayne@69: ** database waits for the callback to be issued before taking any further jpayne@69: ** action (a reasonable assumption), then using this API may cause the jpayne@69: ** application to deadlock. For example, if connection X is waiting for jpayne@69: ** connection Y's transaction to be concluded, and similarly connection jpayne@69: ** Y is waiting on connection X's transaction, then neither connection jpayne@69: ** will proceed and the system may remain deadlocked indefinitely. jpayne@69: ** jpayne@69: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock jpayne@69: ** detection. ^If a given call to sqlite3_unlock_notify() would put the jpayne@69: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no jpayne@69: ** unlock-notify callback is registered. The system is said to be in jpayne@69: ** a deadlocked state if connection A has registered for an unlock-notify jpayne@69: ** callback on the conclusion of connection B's transaction, and connection jpayne@69: ** B has itself registered for an unlock-notify callback when connection jpayne@69: ** A's transaction is concluded. ^Indirect deadlock is also detected, so jpayne@69: ** the system is also considered to be deadlocked if connection B has jpayne@69: ** registered for an unlock-notify callback on the conclusion of connection jpayne@69: ** C's transaction, where connection C is waiting on connection A. ^Any jpayne@69: ** number of levels of indirection are allowed. jpayne@69: ** jpayne@69: ** The "DROP TABLE" Exception jpayne@69: ** jpayne@69: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost jpayne@69: ** always appropriate to call sqlite3_unlock_notify(). There is however, jpayne@69: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, jpayne@69: ** SQLite checks if there are any currently executing SELECT statements jpayne@69: ** that belong to the same connection. If there are, SQLITE_LOCKED is jpayne@69: ** returned. In this case there is no "blocking connection", so invoking jpayne@69: ** sqlite3_unlock_notify() results in the unlock-notify callback being jpayne@69: ** invoked immediately. If the application then re-attempts the "DROP TABLE" jpayne@69: ** or "DROP INDEX" query, an infinite loop might be the result. jpayne@69: ** jpayne@69: ** One way around this problem is to check the extended error code returned jpayne@69: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the jpayne@69: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in jpayne@69: ** the special "DROP TABLE/INDEX" case, the extended error code is just jpayne@69: ** SQLITE_LOCKED.)^ jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_unlock_notify( jpayne@69: sqlite3 *pBlocked, /* Waiting connection */ jpayne@69: void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ jpayne@69: void *pNotifyArg /* Argument to pass to xNotify */ jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: String Comparison jpayne@69: ** jpayne@69: ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications jpayne@69: ** and extensions to compare the contents of two buffers containing UTF-8 jpayne@69: ** strings in a case-independent fashion, using the same definition of "case jpayne@69: ** independence" that SQLite uses internally when comparing identifiers. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stricmp(const char *, const char *); jpayne@69: SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: String Globbing jpayne@69: * jpayne@69: ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if jpayne@69: ** string X matches the [GLOB] pattern P. jpayne@69: ** ^The definition of [GLOB] pattern matching used in jpayne@69: ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the jpayne@69: ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function jpayne@69: ** is case sensitive. jpayne@69: ** jpayne@69: ** Note that this routine returns zero on a match and non-zero if the strings jpayne@69: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_strlike()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: String LIKE Matching jpayne@69: * jpayne@69: ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if jpayne@69: ** string X matches the [LIKE] pattern P with escape character E. jpayne@69: ** ^The definition of [LIKE] pattern matching used in jpayne@69: ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" jpayne@69: ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without jpayne@69: ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. jpayne@69: ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case jpayne@69: ** insensitive - equivalent upper and lower case ASCII characters match jpayne@69: ** one another. jpayne@69: ** jpayne@69: ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though jpayne@69: ** only ASCII characters are case folded. jpayne@69: ** jpayne@69: ** Note that this routine returns zero on a match and non-zero if the strings jpayne@69: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. jpayne@69: ** jpayne@69: ** See also: [sqlite3_strglob()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Error Logging Interface jpayne@69: ** jpayne@69: ** ^The [sqlite3_log()] interface writes a message into the [error log] jpayne@69: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. jpayne@69: ** ^If logging is enabled, the zFormat string and subsequent arguments are jpayne@69: ** used with [sqlite3_snprintf()] to generate the final output string. jpayne@69: ** jpayne@69: ** The sqlite3_log() interface is intended for use by extensions such as jpayne@69: ** virtual tables, collating functions, and SQL functions. While there is jpayne@69: ** nothing to prevent an application from calling sqlite3_log(), doing so jpayne@69: ** is considered bad form. jpayne@69: ** jpayne@69: ** The zFormat string must not be NULL. jpayne@69: ** jpayne@69: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine jpayne@69: ** will not use dynamically allocated memory. The log message is stored in jpayne@69: ** a fixed-length buffer on the stack. If the log message is longer than jpayne@69: ** a few hundred characters, it will be truncated to the length of the jpayne@69: ** buffer. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Write-Ahead Log Commit Hook jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The [sqlite3_wal_hook()] function is used to register a callback that jpayne@69: ** is invoked each time data is committed to a database in wal mode. jpayne@69: ** jpayne@69: ** ^(The callback is invoked by SQLite after the commit has taken place and jpayne@69: ** the associated write-lock on the database released)^, so the implementation jpayne@69: ** may read, write or [checkpoint] the database as required. jpayne@69: ** jpayne@69: ** ^The first parameter passed to the callback function when it is invoked jpayne@69: ** is a copy of the third parameter passed to sqlite3_wal_hook() when jpayne@69: ** registering the callback. ^The second is a copy of the database handle. jpayne@69: ** ^The third parameter is the name of the database that was written to - jpayne@69: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter jpayne@69: ** is the number of pages currently in the write-ahead log file, jpayne@69: ** including those that were just committed. jpayne@69: ** jpayne@69: ** The callback function should normally return [SQLITE_OK]. ^If an error jpayne@69: ** code is returned, that error will propagate back up through the jpayne@69: ** SQLite code base to cause the statement that provoked the callback jpayne@69: ** to report an error, though the commit will have still occurred. If the jpayne@69: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value jpayne@69: ** that does not correspond to any valid SQLite error code, the results jpayne@69: ** are undefined. jpayne@69: ** jpayne@69: ** A single database handle may have at most a single write-ahead log callback jpayne@69: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any jpayne@69: ** previously registered write-ahead log callback. ^The return value is jpayne@69: ** a copy of the third parameter from the previous call, if any, or 0. jpayne@69: ** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the jpayne@69: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will jpayne@69: ** overwrite any prior [sqlite3_wal_hook()] settings. jpayne@69: */ jpayne@69: SQLITE_API void *sqlite3_wal_hook( jpayne@69: sqlite3*, jpayne@69: int(*)(void *,sqlite3*,const char*,int), jpayne@69: void* jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configure an auto-checkpoint jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around jpayne@69: ** [sqlite3_wal_hook()] that causes any database on [database connection] D jpayne@69: ** to automatically [checkpoint] jpayne@69: ** after committing a transaction if there are N or jpayne@69: ** more frames in the [write-ahead log] file. ^Passing zero or jpayne@69: ** a negative value as the nFrame parameter disables automatic jpayne@69: ** checkpoints entirely. jpayne@69: ** jpayne@69: ** ^The callback registered by this function replaces any existing callback jpayne@69: ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback jpayne@69: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism jpayne@69: ** configured by this function. jpayne@69: ** jpayne@69: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface jpayne@69: ** from SQL. jpayne@69: ** jpayne@69: ** ^Checkpoints initiated by this mechanism are jpayne@69: ** [sqlite3_wal_checkpoint_v2|PASSIVE]. jpayne@69: ** jpayne@69: ** ^Every new [database connection] defaults to having the auto-checkpoint jpayne@69: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] jpayne@69: ** pages. The use of this interface jpayne@69: ** is only necessary if the default setting is found to be suboptimal jpayne@69: ** for a particular application. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Checkpoint a database jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to jpayne@69: ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ jpayne@69: ** jpayne@69: ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the jpayne@69: ** [write-ahead log] for database X on [database connection] D to be jpayne@69: ** transferred into the database file and for the write-ahead log to jpayne@69: ** be reset. See the [checkpointing] documentation for addition jpayne@69: ** information. jpayne@69: ** jpayne@69: ** This interface used to be the only way to cause a checkpoint to jpayne@69: ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] jpayne@69: ** interface was added. This interface is retained for backwards jpayne@69: ** compatibility and as a convenience for applications that need to manually jpayne@69: ** start a callback but which do not need the full power (and corresponding jpayne@69: ** complication) of [sqlite3_wal_checkpoint_v2()]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Checkpoint a database jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint jpayne@69: ** operation on database X of [database connection] D in mode M. Status jpayne@69: ** information is written back into integers pointed to by L and C.)^ jpayne@69: ** ^(The M parameter must be a valid [checkpoint mode]:)^ jpayne@69: ** jpayne@69: **
jpayne@69: **
SQLITE_CHECKPOINT_PASSIVE
jpayne@69: ** ^Checkpoint as many frames as possible without waiting for any database jpayne@69: ** readers or writers to finish, then sync the database file if all frames jpayne@69: ** in the log were checkpointed. ^The [busy-handler callback] jpayne@69: ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. jpayne@69: ** ^On the other hand, passive mode might leave the checkpoint unfinished jpayne@69: ** if there are concurrent readers or writers. jpayne@69: ** jpayne@69: **
SQLITE_CHECKPOINT_FULL
jpayne@69: ** ^This mode blocks (it invokes the jpayne@69: ** [sqlite3_busy_handler|busy-handler callback]) until there is no jpayne@69: ** database writer and all readers are reading from the most recent database jpayne@69: ** snapshot. ^It then checkpoints all frames in the log file and syncs the jpayne@69: ** database file. ^This mode blocks new database writers while it is pending, jpayne@69: ** but new database readers are allowed to continue unimpeded. jpayne@69: ** jpayne@69: **
SQLITE_CHECKPOINT_RESTART
jpayne@69: ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition jpayne@69: ** that after checkpointing the log file it blocks (calls the jpayne@69: ** [busy-handler callback]) jpayne@69: ** until all readers are reading from the database file only. ^This ensures jpayne@69: ** that the next writer will restart the log file from the beginning. jpayne@69: ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new jpayne@69: ** database writer attempts while it is pending, but does not impede readers. jpayne@69: ** jpayne@69: **
SQLITE_CHECKPOINT_TRUNCATE
jpayne@69: ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the jpayne@69: ** addition that it also truncates the log file to zero bytes just prior jpayne@69: ** to a successful return. jpayne@69: **
jpayne@69: ** jpayne@69: ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in jpayne@69: ** the log file or to -1 if the checkpoint could not run because jpayne@69: ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not jpayne@69: ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the jpayne@69: ** log file (including any that were already checkpointed before the function jpayne@69: ** was called) or to -1 if the checkpoint could not run due to an error or jpayne@69: ** because the database is not in WAL mode. ^Note that upon successful jpayne@69: ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been jpayne@69: ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. jpayne@69: ** jpayne@69: ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If jpayne@69: ** any other process is running a checkpoint operation at the same time, the jpayne@69: ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a jpayne@69: ** busy-handler configured, it will not be invoked in this case. jpayne@69: ** jpayne@69: ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the jpayne@69: ** exclusive "writer" lock on the database file. ^If the writer lock cannot be jpayne@69: ** obtained immediately, and a busy-handler is configured, it is invoked and jpayne@69: ** the writer lock retried until either the busy-handler returns 0 or the lock jpayne@69: ** is successfully obtained. ^The busy-handler is also invoked while waiting for jpayne@69: ** database readers as described above. ^If the busy-handler returns 0 before jpayne@69: ** the writer lock is obtained or while waiting for database readers, the jpayne@69: ** checkpoint operation proceeds from that point in the same way as jpayne@69: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible jpayne@69: ** without blocking any further. ^SQLITE_BUSY is returned in this case. jpayne@69: ** jpayne@69: ** ^If parameter zDb is NULL or points to a zero length string, then the jpayne@69: ** specified operation is attempted on all WAL databases [attached] to jpayne@69: ** [database connection] db. In this case the jpayne@69: ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If jpayne@69: ** an SQLITE_BUSY error is encountered when processing one or more of the jpayne@69: ** attached WAL databases, the operation is still attempted on any remaining jpayne@69: ** attached databases and SQLITE_BUSY is returned at the end. ^If any other jpayne@69: ** error occurs while processing an attached database, processing is abandoned jpayne@69: ** and the error code is returned to the caller immediately. ^If no error jpayne@69: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached jpayne@69: ** databases, SQLITE_OK is returned. jpayne@69: ** jpayne@69: ** ^If database zDb is the name of an attached database that is not in WAL jpayne@69: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If jpayne@69: ** zDb is not NULL (or a zero length string) and is not the name of any jpayne@69: ** attached database, SQLITE_ERROR is returned to the caller. jpayne@69: ** jpayne@69: ** ^Unless it returns SQLITE_MISUSE, jpayne@69: ** the sqlite3_wal_checkpoint_v2() interface jpayne@69: ** sets the error information that is queried by jpayne@69: ** [sqlite3_errcode()] and [sqlite3_errmsg()]. jpayne@69: ** jpayne@69: ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface jpayne@69: ** from SQL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_wal_checkpoint_v2( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const char *zDb, /* Name of attached database (or NULL) */ jpayne@69: int eMode, /* SQLITE_CHECKPOINT_* value */ jpayne@69: int *pnLog, /* OUT: Size of WAL log in frames */ jpayne@69: int *pnCkpt /* OUT: Total number of frames checkpointed */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Checkpoint Mode Values jpayne@69: ** KEYWORDS: {checkpoint mode} jpayne@69: ** jpayne@69: ** These constants define all valid values for the "checkpoint mode" passed jpayne@69: ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. jpayne@69: ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the jpayne@69: ** meaning of each of these checkpoint modes. jpayne@69: */ jpayne@69: #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ jpayne@69: #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ jpayne@69: #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ jpayne@69: #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Interface Configuration jpayne@69: ** jpayne@69: ** This function may be called by either the [xConnect] or [xCreate] method jpayne@69: ** of a [virtual table] implementation to configure jpayne@69: ** various facets of the virtual table interface. jpayne@69: ** jpayne@69: ** If this interface is invoked outside the context of an xConnect or jpayne@69: ** xCreate virtual table method then the behavior is undefined. jpayne@69: ** jpayne@69: ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the jpayne@69: ** [database connection] in which the virtual table is being created and jpayne@69: ** which is passed in as the first argument to the [xConnect] or [xCreate] jpayne@69: ** method that is invoking sqlite3_vtab_config(). The C parameter is one jpayne@69: ** of the [virtual table configuration options]. The presence and meaning jpayne@69: ** of parameters after C depend on which [virtual table configuration option] jpayne@69: ** is used. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Virtual Table Configuration Options jpayne@69: ** KEYWORDS: {virtual table configuration options} jpayne@69: ** KEYWORDS: {virtual table configuration option} jpayne@69: ** jpayne@69: ** These macros define the various options to the jpayne@69: ** [sqlite3_vtab_config()] interface that [virtual table] implementations jpayne@69: ** can use to customize and optimize their behavior. jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] jpayne@69: **
SQLITE_VTAB_CONSTRAINT_SUPPORT
jpayne@69: **
Calls of the form jpayne@69: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, jpayne@69: ** where X is an integer. If X is zero, then the [virtual table] whose jpayne@69: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not jpayne@69: ** support constraints. In this configuration (which is the default) if jpayne@69: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire jpayne@69: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been jpayne@69: ** specified as part of the users SQL statement, regardless of the actual jpayne@69: ** ON CONFLICT mode specified. jpayne@69: ** jpayne@69: ** If X is non-zero, then the virtual table implementation guarantees jpayne@69: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before jpayne@69: ** any modifications to internal or persistent data structures have been made. jpayne@69: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite jpayne@69: ** is able to roll back a statement or database transaction, and abandon jpayne@69: ** or continue processing the current SQL statement as appropriate. jpayne@69: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns jpayne@69: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode jpayne@69: ** had been ABORT. jpayne@69: ** jpayne@69: ** Virtual table implementations that are required to handle OR REPLACE jpayne@69: ** must do so within the [xUpdate] method. If a call to the jpayne@69: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON jpayne@69: ** CONFLICT policy is REPLACE, the virtual table implementation should jpayne@69: ** silently replace the appropriate rows within the xUpdate callback and jpayne@69: ** return SQLITE_OK. Or, if this is not possible, it may return jpayne@69: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT jpayne@69: ** constraint handling. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_VTAB_DIRECTONLY]]
SQLITE_VTAB_DIRECTONLY
jpayne@69: **
Calls of the form jpayne@69: ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the jpayne@69: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation jpayne@69: ** prohibits that virtual table from being used from within triggers and jpayne@69: ** views. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_VTAB_INNOCUOUS]]
SQLITE_VTAB_INNOCUOUS
jpayne@69: **
Calls of the form jpayne@69: ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the jpayne@69: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation jpayne@69: ** identify that virtual table as being safe to use from within triggers jpayne@69: ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the jpayne@69: ** virtual table can do no serious harm even if it is controlled by a jpayne@69: ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS jpayne@69: ** flag unless absolutely necessary. jpayne@69: **
jpayne@69: ** jpayne@69: ** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]
SQLITE_VTAB_USES_ALL_SCHEMAS
jpayne@69: **
Calls of the form jpayne@69: ** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the jpayne@69: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation jpayne@69: ** instruct the query planner to begin at least a read transaction on jpayne@69: ** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the jpayne@69: ** virtual table is used. jpayne@69: **
jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 jpayne@69: #define SQLITE_VTAB_INNOCUOUS 2 jpayne@69: #define SQLITE_VTAB_DIRECTONLY 3 jpayne@69: #define SQLITE_VTAB_USES_ALL_SCHEMAS 4 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine The Virtual Table Conflict Policy jpayne@69: ** jpayne@69: ** This function may only be called from within a call to the [xUpdate] method jpayne@69: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The jpayne@69: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], jpayne@69: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode jpayne@69: ** of the SQL statement that triggered the call to the [xUpdate] method of the jpayne@69: ** [virtual table]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE jpayne@69: ** jpayne@69: ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] jpayne@69: ** method of a [virtual table], then it might return true if the jpayne@69: ** column is being fetched as part of an UPDATE operation during which the jpayne@69: ** column value will not change. The virtual table implementation can use jpayne@69: ** this hint as permission to substitute a return value that is less jpayne@69: ** expensive to compute and that the corresponding jpayne@69: ** [xUpdate] method understands as a "no-change" value. jpayne@69: ** jpayne@69: ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that jpayne@69: ** the column is not changed by the UPDATE statement, then the xColumn jpayne@69: ** method can optionally return without setting a result, without calling jpayne@69: ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. jpayne@69: ** In that case, [sqlite3_value_nochange(X)] will return true for the jpayne@69: ** same column in the [xUpdate] method. jpayne@69: ** jpayne@69: ** The sqlite3_vtab_nochange() routine is an optimization. Virtual table jpayne@69: ** implementations should continue to give a correct answer even if the jpayne@69: ** sqlite3_vtab_nochange() interface were to always return false. In the jpayne@69: ** current implementation, the sqlite3_vtab_nochange() interface does always jpayne@69: ** returns false for the enhanced [UPDATE FROM] statement. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine The Collation For a Virtual Table Constraint jpayne@69: ** METHOD: sqlite3_index_info jpayne@69: ** jpayne@69: ** This function may only be called from within a call to the [xBestIndex] jpayne@69: ** method of a [virtual table]. This function returns a pointer to a string jpayne@69: ** that is the name of the appropriate collation sequence to use for text jpayne@69: ** comparisons on the constraint identified by its arguments. jpayne@69: ** jpayne@69: ** The first argument must be the pointer to the [sqlite3_index_info] object jpayne@69: ** that is the first parameter to the xBestIndex() method. The second argument jpayne@69: ** must be an index into the aConstraint[] array belonging to the jpayne@69: ** sqlite3_index_info structure passed to xBestIndex. jpayne@69: ** jpayne@69: ** Important: jpayne@69: ** The first parameter must be the same pointer that is passed into the jpayne@69: ** xBestMethod() method. The first parameter may not be a pointer to a jpayne@69: ** different [sqlite3_index_info] object, even an exact copy. jpayne@69: ** jpayne@69: ** The return value is computed as follows: jpayne@69: ** jpayne@69: **
    jpayne@69: **

  1. If the constraint comes from a WHERE clause expression that contains jpayne@69: ** a [COLLATE operator], then the name of the collation specified by jpayne@69: ** that COLLATE operator is returned. jpayne@69: **

  2. If there is no COLLATE operator, but the column that is the subject jpayne@69: ** of the constraint specifies an alternative collating sequence via jpayne@69: ** a [COLLATE clause] on the column definition within the CREATE TABLE jpayne@69: ** statement that was passed into [sqlite3_declare_vtab()], then the jpayne@69: ** name of that alternative collating sequence is returned. jpayne@69: **

  3. Otherwise, "BINARY" is returned. jpayne@69: **

jpayne@69: */ jpayne@69: SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine if a virtual table query is DISTINCT jpayne@69: ** METHOD: sqlite3_index_info jpayne@69: ** jpayne@69: ** This API may only be used from within an [xBestIndex|xBestIndex method] jpayne@69: ** of a [virtual table] implementation. The result of calling this jpayne@69: ** interface from outside of xBestIndex() is undefined and probably harmful. jpayne@69: ** jpayne@69: ** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and jpayne@69: ** 3. The integer returned by sqlite3_vtab_distinct() jpayne@69: ** gives the virtual table additional information about how the query jpayne@69: ** planner wants the output to be ordered. As long as the virtual table jpayne@69: ** can meet the ordering requirements of the query planner, it may set jpayne@69: ** the "orderByConsumed" flag. jpayne@69: ** jpayne@69: **

  1. jpayne@69: ** ^If the sqlite3_vtab_distinct() interface returns 0, that means jpayne@69: ** that the query planner needs the virtual table to return all rows in the jpayne@69: ** sort order defined by the "nOrderBy" and "aOrderBy" fields of the jpayne@69: ** [sqlite3_index_info] object. This is the default expectation. If the jpayne@69: ** virtual table outputs all rows in sorted order, then it is always safe for jpayne@69: ** the xBestIndex method to set the "orderByConsumed" flag, regardless of jpayne@69: ** the return value from sqlite3_vtab_distinct(). jpayne@69: **

  2. jpayne@69: ** ^(If the sqlite3_vtab_distinct() interface returns 1, that means jpayne@69: ** that the query planner does not need the rows to be returned in sorted order jpayne@69: ** as long as all rows with the same values in all columns identified by the jpayne@69: ** "aOrderBy" field are adjacent.)^ This mode is used when the query planner jpayne@69: ** is doing a GROUP BY. jpayne@69: **

  3. jpayne@69: ** ^(If the sqlite3_vtab_distinct() interface returns 2, that means jpayne@69: ** that the query planner does not need the rows returned in any particular jpayne@69: ** order, as long as rows with the same values in all columns identified jpayne@69: ** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows jpayne@69: ** contain the same values for all columns identified by "colUsed", all but jpayne@69: ** one such row may optionally be omitted from the result.)^ jpayne@69: ** The virtual table is not required to omit rows that are duplicates jpayne@69: ** over the "colUsed" columns, but if the virtual table can do that without jpayne@69: ** too much extra effort, it could potentially help the query to run faster. jpayne@69: ** This mode is used for a DISTINCT query. jpayne@69: **

  4. jpayne@69: ** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the jpayne@69: ** virtual table must return rows in the order defined by "aOrderBy" as jpayne@69: ** if the sqlite3_vtab_distinct() interface had returned 0. However if jpayne@69: ** two or more rows in the result have the same values for all columns jpayne@69: ** identified by "colUsed", then all but one such row may optionally be jpayne@69: ** omitted.)^ Like when the return value is 2, the virtual table jpayne@69: ** is not required to omit rows that are duplicates over the "colUsed" jpayne@69: ** columns, but if the virtual table can do that without jpayne@69: ** too much extra effort, it could potentially help the query to run faster. jpayne@69: ** This mode is used for queries jpayne@69: ** that have both DISTINCT and ORDER BY clauses. jpayne@69: **

jpayne@69: ** jpayne@69: **

The following table summarizes the conditions under which the jpayne@69: ** virtual table is allowed to set the "orderByConsumed" flag based on jpayne@69: ** the value returned by sqlite3_vtab_distinct(). This table is a jpayne@69: ** restatement of the previous four paragraphs: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: **
sqlite3_vtab_distinct() return value jpayne@69: ** Rows are returned in aOrderBy order jpayne@69: ** Rows with the same value in all aOrderBy columns are adjacent jpayne@69: ** Duplicates over all colUsed columns may be omitted jpayne@69: **
0yesyesno jpayne@69: **
1noyesno jpayne@69: **
2noyesyes jpayne@69: **
3yesyesyes jpayne@69: **
jpayne@69: ** jpayne@69: ** ^For the purposes of comparing virtual table output values to see if the jpayne@69: ** values are same value for sorting purposes, two NULL values are considered jpayne@69: ** to be the same. In other words, the comparison operator is "IS" jpayne@69: ** (or "IS NOT DISTINCT FROM") and not "==". jpayne@69: ** jpayne@69: ** If a virtual table implementation is unable to meet the requirements jpayne@69: ** specified above, then it must not set the "orderByConsumed" flag in the jpayne@69: ** [sqlite3_index_info] object or an incorrect answer may result. jpayne@69: ** jpayne@69: ** ^A virtual table implementation is always free to return rows in any order jpayne@69: ** it wants, as long as the "orderByConsumed" flag is not set. ^When the jpayne@69: ** the "orderByConsumed" flag is unset, the query planner will add extra jpayne@69: ** [bytecode] to ensure that the final results returned by the SQL query are jpayne@69: ** ordered correctly. The use of the "orderByConsumed" flag and the jpayne@69: ** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful jpayne@69: ** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" jpayne@69: ** flag might help queries against a virtual table to run faster. Being jpayne@69: ** overly aggressive and setting the "orderByConsumed" flag when it is not jpayne@69: ** valid to do so, on the other hand, might cause SQLite to return incorrect jpayne@69: ** results. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Identify and handle IN constraints in xBestIndex jpayne@69: ** jpayne@69: ** This interface may only be used from within an jpayne@69: ** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. jpayne@69: ** The result of invoking this interface from any other context is jpayne@69: ** undefined and probably harmful. jpayne@69: ** jpayne@69: ** ^(A constraint on a virtual table of the form jpayne@69: ** "[IN operator|column IN (...)]" is jpayne@69: ** communicated to the xBestIndex method as a jpayne@69: ** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use jpayne@69: ** this constraint, it must set the corresponding jpayne@69: ** aConstraintUsage[].argvIndex to a positive integer. ^(Then, under jpayne@69: ** the usual mode of handling IN operators, SQLite generates [bytecode] jpayne@69: ** that invokes the [xFilter|xFilter() method] once for each value jpayne@69: ** on the right-hand side of the IN operator.)^ Thus the virtual table jpayne@69: ** only sees a single value from the right-hand side of the IN operator jpayne@69: ** at a time. jpayne@69: ** jpayne@69: ** In some cases, however, it would be advantageous for the virtual jpayne@69: ** table to see all values on the right-hand of the IN operator all at jpayne@69: ** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: jpayne@69: ** jpayne@69: **

    jpayne@69: **

  1. jpayne@69: ** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) jpayne@69: ** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint jpayne@69: ** is an [IN operator] that can be processed all at once. ^In other words, jpayne@69: ** sqlite3_vtab_in() with -1 in the third argument is a mechanism jpayne@69: ** by which the virtual table can ask SQLite if all-at-once processing jpayne@69: ** of the IN operator is even possible. jpayne@69: ** jpayne@69: **

  2. jpayne@69: ** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates jpayne@69: ** to SQLite that the virtual table does or does not want to process jpayne@69: ** the IN operator all-at-once, respectively. ^Thus when the third jpayne@69: ** parameter (F) is non-negative, this interface is the mechanism by jpayne@69: ** which the virtual table tells SQLite how it wants to process the jpayne@69: ** IN operator. jpayne@69: **

jpayne@69: ** jpayne@69: ** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times jpayne@69: ** within the same xBestIndex method call. ^For any given P,N pair, jpayne@69: ** the return value from sqlite3_vtab_in(P,N,F) will always be the same jpayne@69: ** within the same xBestIndex call. ^If the interface returns true jpayne@69: ** (non-zero), that means that the constraint is an IN operator jpayne@69: ** that can be processed all-at-once. ^If the constraint is not an IN jpayne@69: ** operator or cannot be processed all-at-once, then the interface returns jpayne@69: ** false. jpayne@69: ** jpayne@69: ** ^(All-at-once processing of the IN operator is selected if both of the jpayne@69: ** following conditions are met: jpayne@69: ** jpayne@69: **
    jpayne@69: **

  1. The P->aConstraintUsage[N].argvIndex value is set to a positive jpayne@69: ** integer. This is how the virtual table tells SQLite that it wants to jpayne@69: ** use the N-th constraint. jpayne@69: ** jpayne@69: **

  2. The last call to sqlite3_vtab_in(P,N,F) for which F was jpayne@69: ** non-negative had F>=1. jpayne@69: **

)^ jpayne@69: ** jpayne@69: ** ^If either or both of the conditions above are false, then SQLite uses jpayne@69: ** the traditional one-at-a-time processing strategy for the IN constraint. jpayne@69: ** ^If both conditions are true, then the argvIndex-th parameter to the jpayne@69: ** xFilter method will be an [sqlite3_value] that appears to be NULL, jpayne@69: ** but which can be passed to [sqlite3_vtab_in_first()] and jpayne@69: ** [sqlite3_vtab_in_next()] to find all values on the right-hand side jpayne@69: ** of the IN constraint. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Find all elements on the right-hand side of an IN constraint. jpayne@69: ** jpayne@69: ** These interfaces are only useful from within the jpayne@69: ** [xFilter|xFilter() method] of a [virtual table] implementation. jpayne@69: ** The result of invoking these interfaces from any other context jpayne@69: ** is undefined and probably harmful. jpayne@69: ** jpayne@69: ** The X parameter in a call to sqlite3_vtab_in_first(X,P) or jpayne@69: ** sqlite3_vtab_in_next(X,P) should be one of the parameters to the jpayne@69: ** xFilter method which invokes these routines, and specifically jpayne@69: ** a parameter that was previously selected for all-at-once IN constraint jpayne@69: ** processing use the [sqlite3_vtab_in()] interface in the jpayne@69: ** [xBestIndex|xBestIndex method]. ^(If the X parameter is not jpayne@69: ** an xFilter argument that was selected for all-at-once IN constraint jpayne@69: ** processing, then these routines return [SQLITE_ERROR].)^ jpayne@69: ** jpayne@69: ** ^(Use these routines to access all values on the right-hand side jpayne@69: ** of the IN constraint using code like the following: jpayne@69: ** jpayne@69: ** 
jpayne@69: **    for(rc=sqlite3_vtab_in_first(pList, &pVal);
jpayne@69: **        rc==SQLITE_OK && pVal;
jpayne@69: **        rc=sqlite3_vtab_in_next(pList, &pVal)
jpayne@69: **    ){
jpayne@69: **      // do something with pVal
jpayne@69: **    }
jpayne@69: **    if( rc!=SQLITE_OK ){
jpayne@69: **      // an error has occurred
jpayne@69: **    }
jpayne@69: **
)^ jpayne@69: ** jpayne@69: ** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) jpayne@69: ** routines return SQLITE_OK and set *P to point to the first or next value jpayne@69: ** on the RHS of the IN constraint. ^If there are no more values on the jpayne@69: ** right hand side of the IN constraint, then *P is set to NULL and these jpayne@69: ** routines return [SQLITE_DONE]. ^The return value might be jpayne@69: ** some other value, such as SQLITE_NOMEM, in the event of a malfunction. jpayne@69: ** jpayne@69: ** The *ppOut values returned by these routines are only valid until the jpayne@69: ** next call to either of these routines or until the end of the xFilter jpayne@69: ** method from which these routines were called. If the virtual table jpayne@69: ** implementation needs to retain the *ppOut values for longer, it must make jpayne@69: ** copies. The *ppOut values are [protected sqlite3_value|protected]. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); jpayne@69: SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Constraint values in xBestIndex() jpayne@69: ** METHOD: sqlite3_index_info jpayne@69: ** jpayne@69: ** This API may only be used from within the [xBestIndex|xBestIndex method] jpayne@69: ** of a [virtual table] implementation. The result of calling this interface jpayne@69: ** from outside of an xBestIndex method are undefined and probably harmful. jpayne@69: ** jpayne@69: ** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within jpayne@69: ** the [xBestIndex] method of a [virtual table] implementation, with P being jpayne@69: ** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and jpayne@69: ** J being a 0-based index into P->aConstraint[], then this routine jpayne@69: ** attempts to set *V to the value of the right-hand operand of jpayne@69: ** that constraint if the right-hand operand is known. ^If the jpayne@69: ** right-hand operand is not known, then *V is set to a NULL pointer. jpayne@69: ** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if jpayne@69: ** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) jpayne@69: ** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th jpayne@69: ** constraint is not available. ^The sqlite3_vtab_rhs_value() interface jpayne@69: ** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if jpayne@69: ** something goes wrong. jpayne@69: ** jpayne@69: ** The sqlite3_vtab_rhs_value() interface is usually only successful if jpayne@69: ** the right-hand operand of a constraint is a literal value in the original jpayne@69: ** SQL statement. If the right-hand operand is an expression or a reference jpayne@69: ** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() jpayne@69: ** will probably return [SQLITE_NOTFOUND]. jpayne@69: ** jpayne@69: ** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and jpayne@69: ** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such jpayne@69: ** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ jpayne@69: ** jpayne@69: ** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value jpayne@69: ** and remains valid for the duration of the xBestIndex method call. jpayne@69: ** ^When xBestIndex returns, the sqlite3_value object returned by jpayne@69: ** sqlite3_vtab_rhs_value() is automatically deallocated. jpayne@69: ** jpayne@69: ** The "_rhs_" in the name of this routine is an abbreviation for jpayne@69: ** "Right-Hand Side". jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Conflict resolution modes jpayne@69: ** KEYWORDS: {conflict resolution mode} jpayne@69: ** jpayne@69: ** These constants are returned by [sqlite3_vtab_on_conflict()] to jpayne@69: ** inform a [virtual table] implementation what the [ON CONFLICT] mode jpayne@69: ** is for the SQL statement being evaluated. jpayne@69: ** jpayne@69: ** Note that the [SQLITE_IGNORE] constant is also used as a potential jpayne@69: ** return value from the [sqlite3_set_authorizer()] callback and that jpayne@69: ** [SQLITE_ABORT] is also a [result code]. jpayne@69: */ jpayne@69: #define SQLITE_ROLLBACK 1 jpayne@69: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ jpayne@69: #define SQLITE_FAIL 3 jpayne@69: /* #define SQLITE_ABORT 4 // Also an error code */ jpayne@69: #define SQLITE_REPLACE 5 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepared Statement Scan Status Opcodes jpayne@69: ** KEYWORDS: {scanstatus options} jpayne@69: ** jpayne@69: ** The following constants can be used for the T parameter to the jpayne@69: ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a jpayne@69: ** different metric for sqlite3_stmt_scanstatus() to return. jpayne@69: ** jpayne@69: ** When the value returned to V is a string, space to hold that string is jpayne@69: ** managed by the prepared statement S and will be automatically freed when jpayne@69: ** S is finalized. jpayne@69: ** jpayne@69: ** Not all values are available for all query elements. When a value is jpayne@69: ** not available, the output variable is set to -1 if the value is numeric, jpayne@69: ** or to NULL if it is a string (SQLITE_SCANSTAT_NAME). jpayne@69: ** jpayne@69: **
jpayne@69: ** [[SQLITE_SCANSTAT_NLOOP]]
SQLITE_SCANSTAT_NLOOP
jpayne@69: **
^The [sqlite3_int64] variable pointed to by the V parameter will be jpayne@69: ** set to the total number of times that the X-th loop has run.
jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_NVISIT]]
SQLITE_SCANSTAT_NVISIT
jpayne@69: **
^The [sqlite3_int64] variable pointed to by the V parameter will be set jpayne@69: ** to the total number of rows examined by all iterations of the X-th loop.
jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_EST]]
SQLITE_SCANSTAT_EST
jpayne@69: **
^The "double" variable pointed to by the V parameter will be set to the jpayne@69: ** query planner's estimate for the average number of rows output from each jpayne@69: ** iteration of the X-th loop. If the query planner's estimates was accurate, jpayne@69: ** then this value will approximate the quotient NVISIT/NLOOP and the jpayne@69: ** product of this value for all prior loops with the same SELECTID will jpayne@69: ** be the NLOOP value for the current loop. jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_NAME]]
SQLITE_SCANSTAT_NAME
jpayne@69: **
^The "const char *" variable pointed to by the V parameter will be set jpayne@69: ** to a zero-terminated UTF-8 string containing the name of the index or table jpayne@69: ** used for the X-th loop. jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_EXPLAIN]]
SQLITE_SCANSTAT_EXPLAIN
jpayne@69: **
^The "const char *" variable pointed to by the V parameter will be set jpayne@69: ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] jpayne@69: ** description for the X-th loop. jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_SELECTID]]
SQLITE_SCANSTAT_SELECTID
jpayne@69: **
^The "int" variable pointed to by the V parameter will be set to the jpayne@69: ** id for the X-th query plan element. The id value is unique within the jpayne@69: ** statement. The select-id is the same value as is output in the first jpayne@69: ** column of an [EXPLAIN QUERY PLAN] query. jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_PARENTID]]
SQLITE_SCANSTAT_PARENTID
jpayne@69: **
The "int" variable pointed to by the V parameter will be set to the jpayne@69: ** the id of the parent of the current query element, if applicable, or jpayne@69: ** to zero if the query element has no parent. This is the same value as jpayne@69: ** returned in the second column of an [EXPLAIN QUERY PLAN] query. jpayne@69: ** jpayne@69: ** [[SQLITE_SCANSTAT_NCYCLE]]
SQLITE_SCANSTAT_NCYCLE
jpayne@69: **
The sqlite3_int64 output value is set to the number of cycles, jpayne@69: ** according to the processor time-stamp counter, that elapsed while the jpayne@69: ** query element was being processed. This value is not available for jpayne@69: ** all query elements - if it is unavailable the output variable is jpayne@69: ** set to -1. jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_SCANSTAT_NLOOP 0 jpayne@69: #define SQLITE_SCANSTAT_NVISIT 1 jpayne@69: #define SQLITE_SCANSTAT_EST 2 jpayne@69: #define SQLITE_SCANSTAT_NAME 3 jpayne@69: #define SQLITE_SCANSTAT_EXPLAIN 4 jpayne@69: #define SQLITE_SCANSTAT_SELECTID 5 jpayne@69: #define SQLITE_SCANSTAT_PARENTID 6 jpayne@69: #define SQLITE_SCANSTAT_NCYCLE 7 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepared Statement Scan Status jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** These interfaces return information about the predicted and measured jpayne@69: ** performance for pStmt. Advanced applications can use this jpayne@69: ** interface to compare the predicted and the measured performance and jpayne@69: ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. jpayne@69: ** jpayne@69: ** Since this interface is expected to be rarely used, it is only jpayne@69: ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] jpayne@69: ** compile-time option. jpayne@69: ** jpayne@69: ** The "iScanStatusOp" parameter determines which status information to return. jpayne@69: ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior jpayne@69: ** of this interface is undefined. ^The requested measurement is written into jpayne@69: ** a variable pointed to by the "pOut" parameter. jpayne@69: ** jpayne@69: ** The "flags" parameter must be passed a mask of flags. At present only jpayne@69: ** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX jpayne@69: ** is specified, then status information is available for all elements jpayne@69: ** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If jpayne@69: ** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements jpayne@69: ** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of jpayne@69: ** the EXPLAIN QUERY PLAN output) are available. Invoking API jpayne@69: ** sqlite3_stmt_scanstatus() is equivalent to calling jpayne@69: ** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter. jpayne@69: ** jpayne@69: ** Parameter "idx" identifies the specific query element to retrieve statistics jpayne@69: ** for. Query elements are numbered starting from zero. A value of -1 may be jpayne@69: ** to query for statistics regarding the entire query. ^If idx is out of range jpayne@69: ** - less than -1 or greater than or equal to the total number of query jpayne@69: ** elements used to implement the statement - a non-zero value is returned and jpayne@69: ** the variable that pOut points to is unchanged. jpayne@69: ** jpayne@69: ** See also: [sqlite3_stmt_scanstatus_reset()] jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_stmt_scanstatus( jpayne@69: sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ jpayne@69: int idx, /* Index of loop to report on */ jpayne@69: int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ jpayne@69: void *pOut /* Result written here */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_stmt_scanstatus_v2( jpayne@69: sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ jpayne@69: int idx, /* Index of loop to report on */ jpayne@69: int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ jpayne@69: int flags, /* Mask of flags defined below */ jpayne@69: void *pOut /* Result written here */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Prepared Statement Scan Status jpayne@69: ** KEYWORDS: {scan status flags} jpayne@69: */ jpayne@69: #define SQLITE_SCANSTAT_COMPLEX 0x0001 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Zero Scan-Status Counters jpayne@69: ** METHOD: sqlite3_stmt jpayne@69: ** jpayne@69: ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. jpayne@69: ** jpayne@69: ** This API is only available if the library is built with pre-processor jpayne@69: ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flush caches to disk mid-transaction jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^If a write-transaction is open on [database connection] D when the jpayne@69: ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty jpayne@69: ** pages in the pager-cache that are not currently in use are written out jpayne@69: ** to disk. A dirty page may be in use if a database cursor created by an jpayne@69: ** active SQL statement is reading from it, or if it is page 1 of a database jpayne@69: ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] jpayne@69: ** interface flushes caches for all schemas - "main", "temp", and jpayne@69: ** any [attached] databases. jpayne@69: ** jpayne@69: ** ^If this function needs to obtain extra database locks before dirty pages jpayne@69: ** can be flushed to disk, it does so. ^If those locks cannot be obtained jpayne@69: ** immediately and there is a busy-handler callback configured, it is invoked jpayne@69: ** in the usual manner. ^If the required lock still cannot be obtained, then jpayne@69: ** the database is skipped and an attempt made to flush any dirty pages jpayne@69: ** belonging to the next (if any) database. ^If any databases are skipped jpayne@69: ** because locks cannot be obtained, but no other error occurs, this jpayne@69: ** function returns SQLITE_BUSY. jpayne@69: ** jpayne@69: ** ^If any other error occurs while flushing dirty pages to disk (for jpayne@69: ** example an IO error or out-of-memory condition), then processing is jpayne@69: ** abandoned and an SQLite [error code] is returned to the caller immediately. jpayne@69: ** jpayne@69: ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. jpayne@69: ** jpayne@69: ** ^This function does not set the database handle error code or message jpayne@69: ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_db_cacheflush(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: The pre-update hook. jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^These interfaces are only available if SQLite is compiled using the jpayne@69: ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. jpayne@69: ** jpayne@69: ** ^The [sqlite3_preupdate_hook()] interface registers a callback function jpayne@69: ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation jpayne@69: ** on a database table. jpayne@69: ** ^At most one preupdate hook may be registered at a time on a single jpayne@69: ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides jpayne@69: ** the previous setting. jpayne@69: ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] jpayne@69: ** with a NULL pointer as the second parameter. jpayne@69: ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as jpayne@69: ** the first parameter to callbacks. jpayne@69: ** jpayne@69: ** ^The preupdate hook only fires for changes to real database tables; the jpayne@69: ** preupdate hook is not invoked for changes to [virtual tables] or to jpayne@69: ** system tables like sqlite_sequence or sqlite_stat1. jpayne@69: ** jpayne@69: ** ^The second parameter to the preupdate callback is a pointer to jpayne@69: ** the [database connection] that registered the preupdate hook. jpayne@69: ** ^The third parameter to the preupdate callback is one of the constants jpayne@69: ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the jpayne@69: ** kind of update operation that is about to occur. jpayne@69: ** ^(The fourth parameter to the preupdate callback is the name of the jpayne@69: ** database within the database connection that is being modified. This jpayne@69: ** will be "main" for the main database or "temp" for TEMP tables or jpayne@69: ** the name given after the AS keyword in the [ATTACH] statement for attached jpayne@69: ** databases.)^ jpayne@69: ** ^The fifth parameter to the preupdate callback is the name of the jpayne@69: ** table that is being modified. jpayne@69: ** jpayne@69: ** For an UPDATE or DELETE operation on a [rowid table], the sixth jpayne@69: ** parameter passed to the preupdate callback is the initial [rowid] of the jpayne@69: ** row being modified or deleted. For an INSERT operation on a rowid table, jpayne@69: ** or any operation on a WITHOUT ROWID table, the value of the sixth jpayne@69: ** parameter is undefined. For an INSERT or UPDATE on a rowid table the jpayne@69: ** seventh parameter is the final rowid value of the row being inserted jpayne@69: ** or updated. The value of the seventh parameter passed to the callback jpayne@69: ** function is not defined for operations on WITHOUT ROWID tables, or for jpayne@69: ** DELETE operations on rowid tables. jpayne@69: ** jpayne@69: ** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from jpayne@69: ** the previous call on the same [database connection] D, or NULL for jpayne@69: ** the first call on D. jpayne@69: ** jpayne@69: ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], jpayne@69: ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces jpayne@69: ** provide additional information about a preupdate event. These routines jpayne@69: ** may only be called from within a preupdate callback. Invoking any of jpayne@69: ** these routines from outside of a preupdate callback or with a jpayne@69: ** [database connection] pointer that is different from the one supplied jpayne@69: ** to the preupdate callback results in undefined and probably undesirable jpayne@69: ** behavior. jpayne@69: ** jpayne@69: ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns jpayne@69: ** in the row that is being inserted, updated, or deleted. jpayne@69: ** jpayne@69: ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to jpayne@69: ** a [protected sqlite3_value] that contains the value of the Nth column of jpayne@69: ** the table row before it is updated. The N parameter must be between 0 jpayne@69: ** and one less than the number of columns or the behavior will be jpayne@69: ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE jpayne@69: ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the jpayne@69: ** behavior is undefined. The [sqlite3_value] that P points to jpayne@69: ** will be destroyed when the preupdate callback returns. jpayne@69: ** jpayne@69: ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to jpayne@69: ** a [protected sqlite3_value] that contains the value of the Nth column of jpayne@69: ** the table row after it is updated. The N parameter must be between 0 jpayne@69: ** and one less than the number of columns or the behavior will be jpayne@69: ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE jpayne@69: ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the jpayne@69: ** behavior is undefined. The [sqlite3_value] that P points to jpayne@69: ** will be destroyed when the preupdate callback returns. jpayne@69: ** jpayne@69: ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate jpayne@69: ** callback was invoked as a result of a direct insert, update, or delete jpayne@69: ** operation; or 1 for inserts, updates, or deletes invoked by top-level jpayne@69: ** triggers; or 2 for changes resulting from triggers called by top-level jpayne@69: ** triggers; and so forth. jpayne@69: ** jpayne@69: ** When the [sqlite3_blob_write()] API is used to update a blob column, jpayne@69: ** the pre-update hook is invoked with SQLITE_DELETE. This is because the jpayne@69: ** in this case the new values are not available. In this case, when a jpayne@69: ** callback made with op==SQLITE_DELETE is actually a write using the jpayne@69: ** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns jpayne@69: ** the index of the column being written. In other cases, where the jpayne@69: ** pre-update hook is being invoked for some other reason, including a jpayne@69: ** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. jpayne@69: ** jpayne@69: ** See also: [sqlite3_update_hook()] jpayne@69: */ jpayne@69: #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) jpayne@69: SQLITE_API void *sqlite3_preupdate_hook( jpayne@69: sqlite3 *db, jpayne@69: void(*xPreUpdate)( jpayne@69: void *pCtx, /* Copy of third arg to preupdate_hook() */ jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: int op, /* SQLITE_UPDATE, DELETE or INSERT */ jpayne@69: char const *zDb, /* Database name */ jpayne@69: char const *zName, /* Table name */ jpayne@69: sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ jpayne@69: sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ jpayne@69: ), jpayne@69: void* jpayne@69: ); jpayne@69: SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); jpayne@69: SQLITE_API int sqlite3_preupdate_count(sqlite3 *); jpayne@69: SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); jpayne@69: SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); jpayne@69: SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *); jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Low-level system error code jpayne@69: ** METHOD: sqlite3 jpayne@69: ** jpayne@69: ** ^Attempt to return the underlying operating system error code or error jpayne@69: ** number that caused the most recent I/O error or failure to open a file. jpayne@69: ** The return value is OS-dependent. For example, on unix systems, after jpayne@69: ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be jpayne@69: ** called to get back the underlying "errno" that caused the problem, such jpayne@69: ** as ENOSPC, EAUTH, EISDIR, and so forth. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_system_errno(sqlite3*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Database Snapshot jpayne@69: ** KEYWORDS: {snapshot} {sqlite3_snapshot} jpayne@69: ** jpayne@69: ** An instance of the snapshot object records the state of a [WAL mode] jpayne@69: ** database for some specific point in history. jpayne@69: ** jpayne@69: ** In [WAL mode], multiple [database connections] that are open on the jpayne@69: ** same database file can each be reading a different historical version jpayne@69: ** of the database file. When a [database connection] begins a read jpayne@69: ** transaction, that connection sees an unchanging copy of the database jpayne@69: ** as it existed for the point in time when the transaction first started. jpayne@69: ** Subsequent changes to the database from other connections are not seen jpayne@69: ** by the reader until a new read transaction is started. jpayne@69: ** jpayne@69: ** The sqlite3_snapshot object records state information about an historical jpayne@69: ** version of the database file so that it is possible to later open a new read jpayne@69: ** transaction that sees that historical version of the database rather than jpayne@69: ** the most recent version. jpayne@69: */ jpayne@69: typedef struct sqlite3_snapshot { jpayne@69: unsigned char hidden[48]; jpayne@69: } sqlite3_snapshot; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Record A Database Snapshot jpayne@69: ** CONSTRUCTOR: sqlite3_snapshot jpayne@69: ** jpayne@69: ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a jpayne@69: ** new [sqlite3_snapshot] object that records the current state of jpayne@69: ** schema S in database connection D. ^On success, the jpayne@69: ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly jpayne@69: ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. jpayne@69: ** If there is not already a read-transaction open on schema S when jpayne@69: ** this function is called, one is opened automatically. jpayne@69: ** jpayne@69: ** The following must be true for this function to succeed. If any of jpayne@69: ** the following statements are false when sqlite3_snapshot_get() is jpayne@69: ** called, SQLITE_ERROR is returned. The final value of *P is undefined jpayne@69: ** in this case. jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** This function may also return SQLITE_NOMEM. If it is called with the jpayne@69: ** database handle in autocommit mode but fails for some other reason, jpayne@69: ** whether or not a read transaction is opened on schema S is undefined. jpayne@69: ** jpayne@69: ** The [sqlite3_snapshot] object returned from a successful call to jpayne@69: ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] jpayne@69: ** to avoid a memory leak. jpayne@69: ** jpayne@69: ** The [sqlite3_snapshot_get()] interface is only available when the jpayne@69: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( jpayne@69: sqlite3 *db, jpayne@69: const char *zSchema, jpayne@69: sqlite3_snapshot **ppSnapshot jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Start a read transaction on an historical snapshot jpayne@69: ** METHOD: sqlite3_snapshot jpayne@69: ** jpayne@69: ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read jpayne@69: ** transaction or upgrades an existing one for schema S of jpayne@69: ** [database connection] D such that the read transaction refers to jpayne@69: ** historical [snapshot] P, rather than the most recent change to the jpayne@69: ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK jpayne@69: ** on success or an appropriate [error code] if it fails. jpayne@69: ** jpayne@69: ** ^In order to succeed, the database connection must not be in jpayne@69: ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there jpayne@69: ** is already a read transaction open on schema S, then the database handle jpayne@69: ** must have no active statements (SELECT statements that have been passed jpayne@69: ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). jpayne@69: ** SQLITE_ERROR is returned if either of these conditions is violated, or jpayne@69: ** if schema S does not exist, or if the snapshot object is invalid. jpayne@69: ** jpayne@69: ** ^A call to sqlite3_snapshot_open() will fail to open if the specified jpayne@69: ** snapshot has been overwritten by a [checkpoint]. In this case jpayne@69: ** SQLITE_ERROR_SNAPSHOT is returned. jpayne@69: ** jpayne@69: ** If there is already a read transaction open when this function is jpayne@69: ** invoked, then the same read transaction remains open (on the same jpayne@69: ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT jpayne@69: ** is returned. If another error code - for example SQLITE_PROTOCOL or an jpayne@69: ** SQLITE_IOERR error code - is returned, then the final state of the jpayne@69: ** read transaction is undefined. If SQLITE_OK is returned, then the jpayne@69: ** read transaction is now open on database snapshot P. jpayne@69: ** jpayne@69: ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the jpayne@69: ** database connection D does not know that the database file for jpayne@69: ** schema S is in [WAL mode]. A database connection might not know jpayne@69: ** that the database file is in [WAL mode] if there has been no prior jpayne@69: ** I/O on that database connection, or if the database entered [WAL mode] jpayne@69: ** after the most recent I/O on the database connection.)^ jpayne@69: ** (Hint: Run "[PRAGMA application_id]" against a newly opened jpayne@69: ** database connection in order to make it ready to use snapshots.) jpayne@69: ** jpayne@69: ** The [sqlite3_snapshot_open()] interface is only available when the jpayne@69: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( jpayne@69: sqlite3 *db, jpayne@69: const char *zSchema, jpayne@69: sqlite3_snapshot *pSnapshot jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Destroy a snapshot jpayne@69: ** DESTRUCTOR: sqlite3_snapshot jpayne@69: ** jpayne@69: ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. jpayne@69: ** The application must eventually free every [sqlite3_snapshot] object jpayne@69: ** using this routine to avoid a memory leak. jpayne@69: ** jpayne@69: ** The [sqlite3_snapshot_free()] interface is only available when the jpayne@69: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Compare the ages of two snapshot handles. jpayne@69: ** METHOD: sqlite3_snapshot jpayne@69: ** jpayne@69: ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages jpayne@69: ** of two valid snapshot handles. jpayne@69: ** jpayne@69: ** If the two snapshot handles are not associated with the same database jpayne@69: ** file, the result of the comparison is undefined. jpayne@69: ** jpayne@69: ** Additionally, the result of the comparison is only valid if both of the jpayne@69: ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the jpayne@69: ** last time the wal file was deleted. The wal file is deleted when the jpayne@69: ** database is changed back to rollback mode or when the number of database jpayne@69: ** clients drops to zero. If either snapshot handle was obtained before the jpayne@69: ** wal file was last deleted, the value returned by this function jpayne@69: ** is undefined. jpayne@69: ** jpayne@69: ** Otherwise, this API returns a negative value if P1 refers to an older jpayne@69: ** snapshot than P2, zero if the two handles refer to the same database jpayne@69: ** snapshot, and a positive value if P1 is a newer snapshot than P2. jpayne@69: ** jpayne@69: ** This interface is only available if SQLite is compiled with the jpayne@69: ** [SQLITE_ENABLE_SNAPSHOT] option. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( jpayne@69: sqlite3_snapshot *p1, jpayne@69: sqlite3_snapshot *p2 jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Recover snapshots from a wal file jpayne@69: ** METHOD: sqlite3_snapshot jpayne@69: ** jpayne@69: ** If a [WAL file] remains on disk after all database connections close jpayne@69: ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] jpayne@69: ** or because the last process to have the database opened exited without jpayne@69: ** calling [sqlite3_close()]) and a new connection is subsequently opened jpayne@69: ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface jpayne@69: ** will only be able to open the last transaction added to the WAL file jpayne@69: ** even though the WAL file contains other valid transactions. jpayne@69: ** jpayne@69: ** This function attempts to scan the WAL file associated with database zDb jpayne@69: ** of database handle db and make all valid snapshots available to jpayne@69: ** sqlite3_snapshot_open(). It is an error if there is already a read jpayne@69: ** transaction open on the database, or if the database is not a WAL mode jpayne@69: ** database. jpayne@69: ** jpayne@69: ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. jpayne@69: ** jpayne@69: ** This interface is only available if SQLite is compiled with the jpayne@69: ** [SQLITE_ENABLE_SNAPSHOT] option. jpayne@69: */ jpayne@69: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Serialize a database jpayne@69: ** jpayne@69: ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory jpayne@69: ** that is a serialization of the S database on [database connection] D. jpayne@69: ** If P is not a NULL pointer, then the size of the database in bytes jpayne@69: ** is written into *P. jpayne@69: ** jpayne@69: ** For an ordinary on-disk database file, the serialization is just a jpayne@69: ** copy of the disk file. For an in-memory database or a "TEMP" database, jpayne@69: ** the serialization is the same sequence of bytes which would be written jpayne@69: ** to disk if that database where backed up to disk. jpayne@69: ** jpayne@69: ** The usual case is that sqlite3_serialize() copies the serialization of jpayne@69: ** the database into memory obtained from [sqlite3_malloc64()] and returns jpayne@69: ** a pointer to that memory. The caller is responsible for freeing the jpayne@69: ** returned value to avoid a memory leak. However, if the F argument jpayne@69: ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations jpayne@69: ** are made, and the sqlite3_serialize() function will return a pointer jpayne@69: ** to the contiguous memory representation of the database that SQLite jpayne@69: ** is currently using for that database, or NULL if the no such contiguous jpayne@69: ** memory representation of the database exists. A contiguous memory jpayne@69: ** representation of the database will usually only exist if there has jpayne@69: ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same jpayne@69: ** values of D and S. jpayne@69: ** The size of the database is written into *P even if the jpayne@69: ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy jpayne@69: ** of the database exists. jpayne@69: ** jpayne@69: ** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set, jpayne@69: ** the returned buffer content will remain accessible and unchanged jpayne@69: ** until either the next write operation on the connection or when jpayne@69: ** the connection is closed, and applications must not modify the jpayne@69: ** buffer. If the bit had been clear, the returned buffer will not jpayne@69: ** be accessed by SQLite after the call. jpayne@69: ** jpayne@69: ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the jpayne@69: ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory jpayne@69: ** allocation error occurs. jpayne@69: ** jpayne@69: ** This interface is omitted if SQLite is compiled with the jpayne@69: ** [SQLITE_OMIT_DESERIALIZE] option. jpayne@69: */ jpayne@69: SQLITE_API unsigned char *sqlite3_serialize( jpayne@69: sqlite3 *db, /* The database connection */ jpayne@69: const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ jpayne@69: sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ jpayne@69: unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for sqlite3_serialize jpayne@69: ** jpayne@69: ** Zero or more of the following constants can be OR-ed together for jpayne@69: ** the F argument to [sqlite3_serialize(D,S,P,F)]. jpayne@69: ** jpayne@69: ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return jpayne@69: ** a pointer to contiguous in-memory database that it is currently using, jpayne@69: ** without making a copy of the database. If SQLite is not currently using jpayne@69: ** a contiguous in-memory database, then this option causes jpayne@69: ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be jpayne@69: ** using a contiguous in-memory database if it has been initialized by a jpayne@69: ** prior call to [sqlite3_deserialize()]. jpayne@69: */ jpayne@69: #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Deserialize a database jpayne@69: ** jpayne@69: ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the jpayne@69: ** [database connection] D to disconnect from database S and then jpayne@69: ** reopen S as an in-memory database based on the serialization contained jpayne@69: ** in P. The serialized database P is N bytes in size. M is the size of jpayne@69: ** the buffer P, which might be larger than N. If M is larger than N, and jpayne@69: ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is jpayne@69: ** permitted to add content to the in-memory database as long as the total jpayne@69: ** size does not exceed M bytes. jpayne@69: ** jpayne@69: ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will jpayne@69: ** invoke sqlite3_free() on the serialization buffer when the database jpayne@69: ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then jpayne@69: ** SQLite will try to increase the buffer size using sqlite3_realloc64() jpayne@69: ** if writes on the database cause it to grow larger than M bytes. jpayne@69: ** jpayne@69: ** Applications must not modify the buffer P or invalidate it before jpayne@69: ** the database connection D is closed. jpayne@69: ** jpayne@69: ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the jpayne@69: ** database is currently in a read transaction or is involved in a backup jpayne@69: ** operation. jpayne@69: ** jpayne@69: ** It is not possible to deserialized into the TEMP database. If the jpayne@69: ** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the jpayne@69: ** function returns SQLITE_ERROR. jpayne@69: ** jpayne@69: ** The deserialized database should not be in [WAL mode]. If the database jpayne@69: ** is in WAL mode, then any attempt to use the database file will result jpayne@69: ** in an [SQLITE_CANTOPEN] error. The application can set the jpayne@69: ** [file format version numbers] (bytes 18 and 19) of the input database P jpayne@69: ** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the jpayne@69: ** database file into rollback mode and work around this limitation. jpayne@69: ** jpayne@69: ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the jpayne@69: ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then jpayne@69: ** [sqlite3_free()] is invoked on argument P prior to returning. jpayne@69: ** jpayne@69: ** This interface is omitted if SQLite is compiled with the jpayne@69: ** [SQLITE_OMIT_DESERIALIZE] option. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_deserialize( jpayne@69: sqlite3 *db, /* The database connection */ jpayne@69: const char *zSchema, /* Which DB to reopen with the deserialization */ jpayne@69: unsigned char *pData, /* The serialized database content */ jpayne@69: sqlite3_int64 szDb, /* Number bytes in the deserialization */ jpayne@69: sqlite3_int64 szBuf, /* Total size of buffer pData[] */ jpayne@69: unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for sqlite3_deserialize() jpayne@69: ** jpayne@69: ** The following are allowed values for 6th argument (the F argument) to jpayne@69: ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. jpayne@69: ** jpayne@69: ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization jpayne@69: ** in the P argument is held in memory obtained from [sqlite3_malloc64()] jpayne@69: ** and that SQLite should take ownership of this memory and automatically jpayne@69: ** free it when it has finished using it. Without this flag, the caller jpayne@69: ** is responsible for freeing any dynamically allocated memory. jpayne@69: ** jpayne@69: ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to jpayne@69: ** grow the size of the database using calls to [sqlite3_realloc64()]. This jpayne@69: ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. jpayne@69: ** Without this flag, the deserialized database cannot increase in size beyond jpayne@69: ** the number of bytes specified by the M parameter. jpayne@69: ** jpayne@69: ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database jpayne@69: ** should be treated as read-only. jpayne@69: */ jpayne@69: #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ jpayne@69: #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ jpayne@69: #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ jpayne@69: jpayne@69: /* jpayne@69: ** Undo the hack that converts floating point types to integer for jpayne@69: ** builds on processors without floating point support. jpayne@69: */ jpayne@69: #ifdef SQLITE_OMIT_FLOATING_POINT jpayne@69: # undef double jpayne@69: #endif jpayne@69: jpayne@69: #if defined(__wasi__) jpayne@69: # undef SQLITE_WASI jpayne@69: # define SQLITE_WASI 1 jpayne@69: # undef SQLITE_OMIT_WAL jpayne@69: # define SQLITE_OMIT_WAL 1/* because it requires shared memory APIs */ jpayne@69: # ifndef SQLITE_OMIT_LOAD_EXTENSION jpayne@69: # define SQLITE_OMIT_LOAD_EXTENSION jpayne@69: # endif jpayne@69: # ifndef SQLITE_THREADSAFE jpayne@69: # define SQLITE_THREADSAFE 0 jpayne@69: # endif jpayne@69: #endif jpayne@69: jpayne@69: #ifdef __cplusplus jpayne@69: } /* End of the 'extern "C"' block */ jpayne@69: #endif jpayne@69: #endif /* SQLITE3_H */ jpayne@69: jpayne@69: /******** Begin file sqlite3rtree.h *********/ jpayne@69: /* jpayne@69: ** 2010 August 30 jpayne@69: ** jpayne@69: ** The author disclaims copyright to this source code. In place of jpayne@69: ** a legal notice, here is a blessing: jpayne@69: ** jpayne@69: ** May you do good and not evil. jpayne@69: ** May you find forgiveness for yourself and forgive others. jpayne@69: ** May you share freely, never taking more than you give. jpayne@69: ** jpayne@69: ************************************************************************* jpayne@69: */ jpayne@69: jpayne@69: #ifndef _SQLITE3RTREE_H_ jpayne@69: #define _SQLITE3RTREE_H_ jpayne@69: jpayne@69: jpayne@69: #ifdef __cplusplus jpayne@69: extern "C" { jpayne@69: #endif jpayne@69: jpayne@69: typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; jpayne@69: typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; jpayne@69: jpayne@69: /* The double-precision datatype used by RTree depends on the jpayne@69: ** SQLITE_RTREE_INT_ONLY compile-time option. jpayne@69: */ jpayne@69: #ifdef SQLITE_RTREE_INT_ONLY jpayne@69: typedef sqlite3_int64 sqlite3_rtree_dbl; jpayne@69: #else jpayne@69: typedef double sqlite3_rtree_dbl; jpayne@69: #endif jpayne@69: jpayne@69: /* jpayne@69: ** Register a geometry callback named zGeom that can be used as part of an jpayne@69: ** R-Tree geometry query as follows: jpayne@69: ** jpayne@69: ** SELECT ... FROM WHERE MATCH $zGeom(... params ...) jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_rtree_geometry_callback( jpayne@69: sqlite3 *db, jpayne@69: const char *zGeom, jpayne@69: int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), jpayne@69: void *pContext jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** A pointer to a structure of the following type is passed as the first jpayne@69: ** argument to callbacks registered using rtree_geometry_callback(). jpayne@69: */ jpayne@69: struct sqlite3_rtree_geometry { jpayne@69: void *pContext; /* Copy of pContext passed to s_r_g_c() */ jpayne@69: int nParam; /* Size of array aParam[] */ jpayne@69: sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ jpayne@69: void *pUser; /* Callback implementation user data */ jpayne@69: void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** Register a 2nd-generation geometry callback named zScore that can be jpayne@69: ** used as part of an R-Tree geometry query as follows: jpayne@69: ** jpayne@69: ** SELECT ... FROM WHERE MATCH $zQueryFunc(... params ...) jpayne@69: */ jpayne@69: SQLITE_API int sqlite3_rtree_query_callback( jpayne@69: sqlite3 *db, jpayne@69: const char *zQueryFunc, jpayne@69: int (*xQueryFunc)(sqlite3_rtree_query_info*), jpayne@69: void *pContext, jpayne@69: void (*xDestructor)(void*) jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** A pointer to a structure of the following type is passed as the jpayne@69: ** argument to scored geometry callback registered using jpayne@69: ** sqlite3_rtree_query_callback(). jpayne@69: ** jpayne@69: ** Note that the first 5 fields of this structure are identical to jpayne@69: ** sqlite3_rtree_geometry. This structure is a subclass of jpayne@69: ** sqlite3_rtree_geometry. jpayne@69: */ jpayne@69: struct sqlite3_rtree_query_info { jpayne@69: void *pContext; /* pContext from when function registered */ jpayne@69: int nParam; /* Number of function parameters */ jpayne@69: sqlite3_rtree_dbl *aParam; /* value of function parameters */ jpayne@69: void *pUser; /* callback can use this, if desired */ jpayne@69: void (*xDelUser)(void*); /* function to free pUser */ jpayne@69: sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ jpayne@69: unsigned int *anQueue; /* Number of pending entries in the queue */ jpayne@69: int nCoord; /* Number of coordinates */ jpayne@69: int iLevel; /* Level of current node or entry */ jpayne@69: int mxLevel; /* The largest iLevel value in the tree */ jpayne@69: sqlite3_int64 iRowid; /* Rowid for current entry */ jpayne@69: sqlite3_rtree_dbl rParentScore; /* Score of parent node */ jpayne@69: int eParentWithin; /* Visibility of parent node */ jpayne@69: int eWithin; /* OUT: Visibility */ jpayne@69: sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ jpayne@69: /* The following fields are only available in 3.8.11 and later */ jpayne@69: sqlite3_value **apSqlParam; /* Original SQL values of parameters */ jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. jpayne@69: */ jpayne@69: #define NOT_WITHIN 0 /* Object completely outside of query region */ jpayne@69: #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ jpayne@69: #define FULLY_WITHIN 2 /* Object fully contained within query region */ jpayne@69: jpayne@69: jpayne@69: #ifdef __cplusplus jpayne@69: } /* end of the 'extern "C"' block */ jpayne@69: #endif jpayne@69: jpayne@69: #endif /* ifndef _SQLITE3RTREE_H_ */ jpayne@69: jpayne@69: /******** End of sqlite3rtree.h *********/ jpayne@69: /******** Begin file sqlite3session.h *********/ jpayne@69: jpayne@69: #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) jpayne@69: #define __SQLITESESSION_H_ 1 jpayne@69: jpayne@69: /* jpayne@69: ** Make sure we can call this stuff from C++. jpayne@69: */ jpayne@69: #ifdef __cplusplus jpayne@69: extern "C" { jpayne@69: #endif jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Session Object Handle jpayne@69: ** jpayne@69: ** An instance of this object is a [session] that can be used to jpayne@69: ** record changes to a database. jpayne@69: */ jpayne@69: typedef struct sqlite3_session sqlite3_session; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Changeset Iterator Handle jpayne@69: ** jpayne@69: ** An instance of this object acts as a cursor for iterating jpayne@69: ** over the elements of a [changeset] or [patchset]. jpayne@69: */ jpayne@69: typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create A New Session Object jpayne@69: ** CONSTRUCTOR: sqlite3_session jpayne@69: ** jpayne@69: ** Create a new session object attached to database handle db. If successful, jpayne@69: ** a pointer to the new object is written to *ppSession and SQLITE_OK is jpayne@69: ** returned. If an error occurs, *ppSession is set to NULL and an SQLite jpayne@69: ** error code (e.g. SQLITE_NOMEM) is returned. jpayne@69: ** jpayne@69: ** It is possible to create multiple session objects attached to a single jpayne@69: ** database handle. jpayne@69: ** jpayne@69: ** Session objects created using this function should be deleted using the jpayne@69: ** [sqlite3session_delete()] function before the database handle that they jpayne@69: ** are attached to is itself closed. If the database handle is closed before jpayne@69: ** the session object is deleted, then the results of calling any session jpayne@69: ** module function, including [sqlite3session_delete()] on the session object jpayne@69: ** are undefined. jpayne@69: ** jpayne@69: ** Because the session module uses the [sqlite3_preupdate_hook()] API, it jpayne@69: ** is not possible for an application to register a pre-update hook on a jpayne@69: ** database handle that has one or more session objects attached. Nor is jpayne@69: ** it possible to create a session object attached to a database handle for jpayne@69: ** which a pre-update hook is already defined. The results of attempting jpayne@69: ** either of these things are undefined. jpayne@69: ** jpayne@69: ** The session object will be used to create changesets for tables in jpayne@69: ** database zDb, where zDb is either "main", or "temp", or the name of an jpayne@69: ** attached database. It is not an error if database zDb is not attached jpayne@69: ** to the database when the session object is created. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_create( jpayne@69: sqlite3 *db, /* Database handle */ jpayne@69: const char *zDb, /* Name of db (e.g. "main") */ jpayne@69: sqlite3_session **ppSession /* OUT: New session object */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Delete A Session Object jpayne@69: ** DESTRUCTOR: sqlite3_session jpayne@69: ** jpayne@69: ** Delete a session object previously allocated using jpayne@69: ** [sqlite3session_create()]. Once a session object has been deleted, the jpayne@69: ** results of attempting to use pSession with any other session module jpayne@69: ** function are undefined. jpayne@69: ** jpayne@69: ** Session objects must be deleted before the database handle to which they jpayne@69: ** are attached is closed. Refer to the documentation for jpayne@69: ** [sqlite3session_create()] for details. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configure a Session Object jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** This method is used to configure a session object after it has been jpayne@69: ** created. At present the only valid values for the second parameter are jpayne@69: ** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID]. jpayne@69: ** jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Options for sqlite3session_object_config jpayne@69: ** jpayne@69: ** The following values may passed as the the 2nd parameter to jpayne@69: ** sqlite3session_object_config(). jpayne@69: ** jpayne@69: **
SQLITE_SESSION_OBJCONFIG_SIZE
jpayne@69: ** This option is used to set, clear or query the flag that enables jpayne@69: ** the [sqlite3session_changeset_size()] API. Because it imposes some jpayne@69: ** computational overhead, this API is disabled by default. Argument jpayne@69: ** pArg must point to a value of type (int). If the value is initially jpayne@69: ** 0, then the sqlite3session_changeset_size() API is disabled. If it jpayne@69: ** is greater than 0, then the same API is enabled. Or, if the initial jpayne@69: ** value is less than zero, no change is made. In all cases the (int) jpayne@69: ** variable is set to 1 if the sqlite3session_changeset_size() API is jpayne@69: ** enabled following the current call, or 0 otherwise. jpayne@69: ** jpayne@69: ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after jpayne@69: ** the first table has been attached to the session object. jpayne@69: ** jpayne@69: **
SQLITE_SESSION_OBJCONFIG_ROWID
jpayne@69: ** This option is used to set, clear or query the flag that enables jpayne@69: ** collection of data for tables with no explicit PRIMARY KEY. jpayne@69: ** jpayne@69: ** Normally, tables with no explicit PRIMARY KEY are simply ignored jpayne@69: ** by the sessions module. However, if this flag is set, it behaves jpayne@69: ** as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted jpayne@69: ** as their leftmost columns. jpayne@69: ** jpayne@69: ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after jpayne@69: ** the first table has been attached to the session object. jpayne@69: */ jpayne@69: #define SQLITE_SESSION_OBJCONFIG_SIZE 1 jpayne@69: #define SQLITE_SESSION_OBJCONFIG_ROWID 2 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Enable Or Disable A Session Object jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** Enable or disable the recording of changes by a session object. When jpayne@69: ** enabled, a session object records changes made to the database. When jpayne@69: ** disabled - it does not. A newly created session object is enabled. jpayne@69: ** Refer to the documentation for [sqlite3session_changeset()] for further jpayne@69: ** details regarding how enabling and disabling a session object affects jpayne@69: ** the eventual changesets. jpayne@69: ** jpayne@69: ** Passing zero to this function disables the session. Passing a value jpayne@69: ** greater than zero enables it. Passing a value less than zero is a jpayne@69: ** no-op, and may be used to query the current state of the session. jpayne@69: ** jpayne@69: ** The return value indicates the final state of the session object: 0 if jpayne@69: ** the session is disabled, or 1 if it is enabled. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Set Or Clear the Indirect Change Flag jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** Each change recorded by a session object is marked as either direct or jpayne@69: ** indirect. A change is marked as indirect if either: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • The session object "indirect" flag is set when the change is jpayne@69: ** made, or jpayne@69: **
  • The change is made by an SQL trigger or foreign key action jpayne@69: ** instead of directly as a result of a users SQL statement. jpayne@69: **
jpayne@69: ** jpayne@69: ** If a single row is affected by more than one operation within a session, jpayne@69: ** then the change is considered indirect if all operations meet the criteria jpayne@69: ** for an indirect change above, or direct otherwise. jpayne@69: ** jpayne@69: ** This function is used to set, clear or query the session object indirect jpayne@69: ** flag. If the second argument passed to this function is zero, then the jpayne@69: ** indirect flag is cleared. If it is greater than zero, the indirect flag jpayne@69: ** is set. Passing a value less than zero does not modify the current value jpayne@69: ** of the indirect flag, and may be used to query the current state of the jpayne@69: ** indirect flag for the specified session object. jpayne@69: ** jpayne@69: ** The return value indicates the final state of the indirect flag: 0 if jpayne@69: ** it is clear, or 1 if it is set. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Attach A Table To A Session Object jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** If argument zTab is not NULL, then it is the name of a table to attach jpayne@69: ** to the session object passed as the first argument. All subsequent changes jpayne@69: ** made to the table while the session object is enabled will be recorded. See jpayne@69: ** documentation for [sqlite3session_changeset()] for further details. jpayne@69: ** jpayne@69: ** Or, if argument zTab is NULL, then changes are recorded for all tables jpayne@69: ** in the database. If additional tables are added to the database (by jpayne@69: ** executing "CREATE TABLE" statements) after this call is made, changes for jpayne@69: ** the new tables are also recorded. jpayne@69: ** jpayne@69: ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly jpayne@69: ** defined as part of their CREATE TABLE statement. It does not matter if the jpayne@69: ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY jpayne@69: ** KEY may consist of a single column, or may be a composite key. jpayne@69: ** jpayne@69: ** It is not an error if the named table does not exist in the database. Nor jpayne@69: ** is it an error if the named table does not have a PRIMARY KEY. However, jpayne@69: ** no changes will be recorded in either of these scenarios. jpayne@69: ** jpayne@69: ** Changes are not recorded for individual rows that have NULL values stored jpayne@69: ** in one or more of their PRIMARY KEY columns. jpayne@69: ** jpayne@69: ** SQLITE_OK is returned if the call completes without error. Or, if an error jpayne@69: ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. jpayne@69: ** jpayne@69: **

Special sqlite_stat1 Handling

jpayne@69: ** jpayne@69: ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to jpayne@69: ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: jpayne@69: ** 
jpayne@69: **        CREATE TABLE sqlite_stat1(tbl,idx,stat)
jpayne@69: **
jpayne@69: ** jpayne@69: ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are jpayne@69: ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes jpayne@69: ** are recorded for rows for which (idx IS NULL) is true. However, for such jpayne@69: ** rows a zero-length blob (SQL value X'') is stored in the changeset or jpayne@69: ** patchset instead of a NULL value. This allows such changesets to be jpayne@69: ** manipulated by legacy implementations of sqlite3changeset_invert(), jpayne@69: ** concat() and similar. jpayne@69: ** jpayne@69: ** The sqlite3changeset_apply() function automatically converts the jpayne@69: ** zero-length blob back to a NULL value when updating the sqlite_stat1 jpayne@69: ** table. However, if the application calls sqlite3changeset_new(), jpayne@69: ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset jpayne@69: ** iterator directly (including on a changeset iterator passed to a jpayne@69: ** conflict-handler callback) then the X'' value is returned. The application jpayne@69: ** must translate X'' to NULL itself if required. jpayne@69: ** jpayne@69: ** Legacy (older than 3.22.0) versions of the sessions module cannot capture jpayne@69: ** changes made to the sqlite_stat1 table. Legacy versions of the jpayne@69: ** sqlite3changeset_apply() function silently ignore any modifications to the jpayne@69: ** sqlite_stat1 table that are part of a changeset or patchset. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_attach( jpayne@69: sqlite3_session *pSession, /* Session object */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Set a table filter on a Session Object. jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** The second argument (xFilter) is the "filter callback". For changes to rows jpayne@69: ** in tables that are not attached to the Session object, the filter is called jpayne@69: ** to determine whether changes to the table's rows should be tracked or not. jpayne@69: ** If xFilter returns 0, changes are not tracked. Note that once a table is jpayne@69: ** attached, xFilter will not be called again. jpayne@69: */ jpayne@69: SQLITE_API void sqlite3session_table_filter( jpayne@69: sqlite3_session *pSession, /* Session object */ jpayne@69: int(*xFilter)( jpayne@69: void *pCtx, /* Copy of third arg to _filter_table() */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ), jpayne@69: void *pCtx /* First argument passed to xFilter */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Generate A Changeset From A Session Object jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** Obtain a changeset containing changes to the tables attached to the jpayne@69: ** session object passed as the first argument. If successful, jpayne@69: ** set *ppChangeset to point to a buffer containing the changeset jpayne@69: ** and *pnChangeset to the size of the changeset in bytes before returning jpayne@69: ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to jpayne@69: ** zero and return an SQLite error code. jpayne@69: ** jpayne@69: ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, jpayne@69: ** each representing a change to a single row of an attached table. An INSERT jpayne@69: ** change contains the values of each field of a new database row. A DELETE jpayne@69: ** contains the original values of each field of a deleted database row. An jpayne@69: ** UPDATE change contains the original values of each field of an updated jpayne@69: ** database row along with the updated values for each updated non-primary-key jpayne@69: ** column. It is not possible for an UPDATE change to represent a change that jpayne@69: ** modifies the values of primary key columns. If such a change is made, it jpayne@69: ** is represented in a changeset as a DELETE followed by an INSERT. jpayne@69: ** jpayne@69: ** Changes are not recorded for rows that have NULL values stored in one or jpayne@69: ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, jpayne@69: ** no corresponding change is present in the changesets returned by this jpayne@69: ** function. If an existing row with one or more NULL values stored in jpayne@69: ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, jpayne@69: ** only an INSERT is appears in the changeset. Similarly, if an existing row jpayne@69: ** with non-NULL PRIMARY KEY values is updated so that one or more of its jpayne@69: ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a jpayne@69: ** DELETE change only. jpayne@69: ** jpayne@69: ** The contents of a changeset may be traversed using an iterator created jpayne@69: ** using the [sqlite3changeset_start()] API. A changeset may be applied to jpayne@69: ** a database with a compatible schema using the [sqlite3changeset_apply()] jpayne@69: ** API. jpayne@69: ** jpayne@69: ** Within a changeset generated by this function, all changes related to a jpayne@69: ** single table are grouped together. In other words, when iterating through jpayne@69: ** a changeset or when applying a changeset to a database, all changes related jpayne@69: ** to a single table are processed before moving on to the next table. Tables jpayne@69: ** are sorted in the same order in which they were attached (or auto-attached) jpayne@69: ** to the sqlite3_session object. The order in which the changes related to jpayne@69: ** a single table are stored is undefined. jpayne@69: ** jpayne@69: ** Following a successful call to this function, it is the responsibility of jpayne@69: ** the caller to eventually free the buffer that *ppChangeset points to using jpayne@69: ** [sqlite3_free()]. jpayne@69: ** jpayne@69: **

Changeset Generation

jpayne@69: ** jpayne@69: ** Once a table has been attached to a session object, the session object jpayne@69: ** records the primary key values of all new rows inserted into the table. jpayne@69: ** It also records the original primary key and other column values of any jpayne@69: ** deleted or updated rows. For each unique primary key value, data is only jpayne@69: ** recorded once - the first time a row with said primary key is inserted, jpayne@69: ** updated or deleted in the lifetime of the session. jpayne@69: ** jpayne@69: ** There is one exception to the previous paragraph: when a row is inserted, jpayne@69: ** updated or deleted, if one or more of its primary key columns contain a jpayne@69: ** NULL value, no record of the change is made. jpayne@69: ** jpayne@69: ** The session object therefore accumulates two types of records - those jpayne@69: ** that consist of primary key values only (created when the user inserts jpayne@69: ** a new record) and those that consist of the primary key values and the jpayne@69: ** original values of other table columns (created when the users deletes jpayne@69: ** or updates a record). jpayne@69: ** jpayne@69: ** When this function is called, the requested changeset is created using jpayne@69: ** both the accumulated records and the current contents of the database jpayne@69: ** file. Specifically: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • For each record generated by an insert, the database is queried jpayne@69: ** for a row with a matching primary key. If one is found, an INSERT jpayne@69: ** change is added to the changeset. If no such row is found, no change jpayne@69: ** is added to the changeset. jpayne@69: ** jpayne@69: **
  • For each record generated by an update or delete, the database is jpayne@69: ** queried for a row with a matching primary key. If such a row is jpayne@69: ** found and one or more of the non-primary key fields have been jpayne@69: ** modified from their original values, an UPDATE change is added to jpayne@69: ** the changeset. Or, if no such row is found in the table, a DELETE jpayne@69: ** change is added to the changeset. If there is a row with a matching jpayne@69: ** primary key in the database, but all fields contain their original jpayne@69: ** values, no change is added to the changeset. jpayne@69: **
jpayne@69: ** jpayne@69: ** This means, amongst other things, that if a row is inserted and then later jpayne@69: ** deleted while a session object is active, neither the insert nor the delete jpayne@69: ** will be present in the changeset. Or if a row is deleted and then later a jpayne@69: ** row with the same primary key values inserted while a session object is jpayne@69: ** active, the resulting changeset will contain an UPDATE change instead of jpayne@69: ** a DELETE and an INSERT. jpayne@69: ** jpayne@69: ** When a session object is disabled (see the [sqlite3session_enable()] API), jpayne@69: ** it does not accumulate records when rows are inserted, updated or deleted. jpayne@69: ** This may appear to have some counter-intuitive effects if a single row jpayne@69: ** is written to more than once during a session. For example, if a row jpayne@69: ** is inserted while a session object is enabled, then later deleted while jpayne@69: ** the same session object is disabled, no INSERT record will appear in the jpayne@69: ** changeset, even though the delete took place while the session was disabled. jpayne@69: ** Or, if one field of a row is updated while a session is disabled, and jpayne@69: ** another field of the same row is updated while the session is enabled, the jpayne@69: ** resulting changeset will contain an UPDATE change that updates both fields. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_changeset( jpayne@69: sqlite3_session *pSession, /* Session object */ jpayne@69: int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ jpayne@69: void **ppChangeset /* OUT: Buffer containing changeset */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Return An Upper-limit For The Size Of The Changeset jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** By default, this function always returns 0. For it to return jpayne@69: ** a useful result, the sqlite3_session object must have been configured jpayne@69: ** to enable this API using sqlite3session_object_config() with the jpayne@69: ** SQLITE_SESSION_OBJCONFIG_SIZE verb. jpayne@69: ** jpayne@69: ** When enabled, this function returns an upper limit, in bytes, for the size jpayne@69: ** of the changeset that might be produced if sqlite3session_changeset() were jpayne@69: ** called. The final changeset size might be equal to or smaller than the jpayne@69: ** size in bytes returned by this function. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Load The Difference Between Tables Into A Session jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** If it is not already attached to the session object passed as the first jpayne@69: ** argument, this function attaches table zTbl in the same manner as the jpayne@69: ** [sqlite3session_attach()] function. If zTbl does not exist, or if it jpayne@69: ** does not have a primary key, this function is a no-op (but does not return jpayne@69: ** an error). jpayne@69: ** jpayne@69: ** Argument zFromDb must be the name of a database ("main", "temp" etc.) jpayne@69: ** attached to the same database handle as the session object that contains jpayne@69: ** a table compatible with the table attached to the session by this function. jpayne@69: ** A table is considered compatible if it: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • Has the same name, jpayne@69: **
  • Has the same set of columns declared in the same order, and jpayne@69: **
  • Has the same PRIMARY KEY definition. jpayne@69: **
jpayne@69: ** jpayne@69: ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables jpayne@69: ** are compatible but do not have any PRIMARY KEY columns, it is not an error jpayne@69: ** but no changes are added to the session object. As with other session jpayne@69: ** APIs, tables without PRIMARY KEYs are simply ignored. jpayne@69: ** jpayne@69: ** This function adds a set of changes to the session object that could be jpayne@69: ** used to update the table in database zFrom (call this the "from-table") jpayne@69: ** so that its content is the same as the table attached to the session jpayne@69: ** object (call this the "to-table"). Specifically: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • For each row (primary key) that exists in the to-table but not in jpayne@69: ** the from-table, an INSERT record is added to the session object. jpayne@69: ** jpayne@69: **
  • For each row (primary key) that exists in the to-table but not in jpayne@69: ** the from-table, a DELETE record is added to the session object. jpayne@69: ** jpayne@69: **
  • For each row (primary key) that exists in both tables, but features jpayne@69: ** different non-PK values in each, an UPDATE record is added to the jpayne@69: ** session. jpayne@69: **
jpayne@69: ** jpayne@69: ** To clarify, if this function is called and then a changeset constructed jpayne@69: ** using [sqlite3session_changeset()], then after applying that changeset to jpayne@69: ** database zFrom the contents of the two compatible tables would be jpayne@69: ** identical. jpayne@69: ** jpayne@69: ** It an error if database zFrom does not exist or does not contain the jpayne@69: ** required compatible table. jpayne@69: ** jpayne@69: ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite jpayne@69: ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg jpayne@69: ** may be set to point to a buffer containing an English language error jpayne@69: ** message. It is the responsibility of the caller to free this buffer using jpayne@69: ** sqlite3_free(). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_diff( jpayne@69: sqlite3_session *pSession, jpayne@69: const char *zFromDb, jpayne@69: const char *zTbl, jpayne@69: char **pzErrMsg jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Generate A Patchset From A Session Object jpayne@69: ** METHOD: sqlite3_session jpayne@69: ** jpayne@69: ** The differences between a patchset and a changeset are that: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • DELETE records consist of the primary key fields only. The jpayne@69: ** original values of other fields are omitted. jpayne@69: **
  • The original values of any modified fields are omitted from jpayne@69: ** UPDATE records. jpayne@69: **
jpayne@69: ** jpayne@69: ** A patchset blob may be used with up to date versions of all jpayne@69: ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), jpayne@69: ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, jpayne@69: ** attempting to use a patchset blob with old versions of the jpayne@69: ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. jpayne@69: ** jpayne@69: ** Because the non-primary key "old.*" fields are omitted, no jpayne@69: ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset jpayne@69: ** is passed to the sqlite3changeset_apply() API. Other conflict types work jpayne@69: ** in the same way as for changesets. jpayne@69: ** jpayne@69: ** Changes within a patchset are ordered in the same way as for changesets jpayne@69: ** generated by the sqlite3session_changeset() function (i.e. all changes for jpayne@69: ** a single table are grouped together, tables appear in the order in which jpayne@69: ** they were attached to the session object). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_patchset( jpayne@69: sqlite3_session *pSession, /* Session object */ jpayne@69: int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ jpayne@69: void **ppPatchset /* OUT: Buffer containing patchset */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Test if a changeset has recorded any changes. jpayne@69: ** jpayne@69: ** Return non-zero if no changes to attached tables have been recorded by jpayne@69: ** the session object passed as the first argument. Otherwise, if one or jpayne@69: ** more changes have been recorded, return zero. jpayne@69: ** jpayne@69: ** Even if this function returns zero, it is possible that calling jpayne@69: ** [sqlite3session_changeset()] on the session handle may still return a jpayne@69: ** changeset that contains no changes. This can happen when a row in jpayne@69: ** an attached table is modified and then later on the original values jpayne@69: ** are restored. However, if this function returns non-zero, then it is jpayne@69: ** guaranteed that a call to sqlite3session_changeset() will return a jpayne@69: ** changeset containing zero changes. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Query for the amount of heap memory used by a session object. jpayne@69: ** jpayne@69: ** This API returns the total amount of heap memory in bytes currently jpayne@69: ** used by the session object passed as the only argument. jpayne@69: */ jpayne@69: SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create An Iterator To Traverse A Changeset jpayne@69: ** CONSTRUCTOR: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** Create an iterator used to iterate through the contents of a changeset. jpayne@69: ** If successful, *pp is set to point to the iterator handle and SQLITE_OK jpayne@69: ** is returned. Otherwise, if an error occurs, *pp is set to zero and an jpayne@69: ** SQLite error code is returned. jpayne@69: ** jpayne@69: ** The following functions can be used to advance and query a changeset jpayne@69: ** iterator created by this function: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • [sqlite3changeset_next()] jpayne@69: **
  • [sqlite3changeset_op()] jpayne@69: **
  • [sqlite3changeset_new()] jpayne@69: **
  • [sqlite3changeset_old()] jpayne@69: **
jpayne@69: ** jpayne@69: ** It is the responsibility of the caller to eventually destroy the iterator jpayne@69: ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the jpayne@69: ** changeset (pChangeset) must remain valid until after the iterator is jpayne@69: ** destroyed. jpayne@69: ** jpayne@69: ** Assuming the changeset blob was created by one of the jpayne@69: ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or jpayne@69: ** [sqlite3changeset_invert()] functions, all changes within the changeset jpayne@69: ** that apply to a single table are grouped together. This means that when jpayne@69: ** an application iterates through a changeset using an iterator created by jpayne@69: ** this function, all changes that relate to a single table are visited jpayne@69: ** consecutively. There is no chance that the iterator will visit a change jpayne@69: ** the applies to table X, then one for table Y, and then later on visit jpayne@69: ** another change for table X. jpayne@69: ** jpayne@69: ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent jpayne@69: ** may be modified by passing a combination of jpayne@69: ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. jpayne@69: ** jpayne@69: ** Note that the sqlite3changeset_start_v2() API is still experimental jpayne@69: ** and therefore subject to change. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_start( jpayne@69: sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ jpayne@69: int nChangeset, /* Size of changeset blob in bytes */ jpayne@69: void *pChangeset /* Pointer to blob containing changeset */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_start_v2( jpayne@69: sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ jpayne@69: int nChangeset, /* Size of changeset blob in bytes */ jpayne@69: void *pChangeset, /* Pointer to blob containing changeset */ jpayne@69: int flags /* SESSION_CHANGESETSTART_* flags */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for sqlite3changeset_start_v2 jpayne@69: ** jpayne@69: ** The following flags may passed via the 4th parameter to jpayne@69: ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: jpayne@69: ** jpayne@69: **
SQLITE_CHANGESETAPPLY_INVERT
jpayne@69: ** Invert the changeset while iterating through it. This is equivalent to jpayne@69: ** inverting a changeset using sqlite3changeset_invert() before applying it. jpayne@69: ** It is an error to specify this flag with a patchset. jpayne@69: */ jpayne@69: #define SQLITE_CHANGESETSTART_INVERT 0x0002 jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Advance A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** This function may only be used with iterators created by the function jpayne@69: ** [sqlite3changeset_start()]. If it is called on an iterator passed to jpayne@69: ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE jpayne@69: ** is returned and the call has no effect. jpayne@69: ** jpayne@69: ** Immediately after an iterator is created by sqlite3changeset_start(), it jpayne@69: ** does not point to any change in the changeset. Assuming the changeset jpayne@69: ** is not empty, the first call to this function advances the iterator to jpayne@69: ** point to the first change in the changeset. Each subsequent call advances jpayne@69: ** the iterator to point to the next change in the changeset (if any). If jpayne@69: ** no error occurs and the iterator points to a valid change after a call jpayne@69: ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. jpayne@69: ** Otherwise, if all changes in the changeset have already been visited, jpayne@69: ** SQLITE_DONE is returned. jpayne@69: ** jpayne@69: ** If an error occurs, an SQLite error code is returned. Possible error jpayne@69: ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or jpayne@69: ** SQLITE_NOMEM. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** The pIter argument passed to this function may either be an iterator jpayne@69: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator jpayne@69: ** created by [sqlite3changeset_start()]. In the latter case, the most recent jpayne@69: ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this jpayne@69: ** is not the case, this function returns [SQLITE_MISUSE]. jpayne@69: ** jpayne@69: ** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three jpayne@69: ** outputs are set through these pointers: jpayne@69: ** jpayne@69: ** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], jpayne@69: ** depending on the type of change that the iterator currently points to; jpayne@69: ** jpayne@69: ** *pnCol is set to the number of columns in the table affected by the change; and jpayne@69: ** jpayne@69: ** *pzTab is set to point to a nul-terminated utf-8 encoded string containing jpayne@69: ** the name of the table affected by the current change. The buffer remains jpayne@69: ** valid until either sqlite3changeset_next() is called on the iterator jpayne@69: ** or until the conflict-handler function returns. jpayne@69: ** jpayne@69: ** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change jpayne@69: ** is an indirect change, or false (0) otherwise. See the documentation for jpayne@69: ** [sqlite3session_indirect()] for a description of direct and indirect jpayne@69: ** changes. jpayne@69: ** jpayne@69: ** If no error occurs, SQLITE_OK is returned. If an error does occur, an jpayne@69: ** SQLite error code is returned. The values of the output variables may not jpayne@69: ** be trusted in this case. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_op( jpayne@69: sqlite3_changeset_iter *pIter, /* Iterator object */ jpayne@69: const char **pzTab, /* OUT: Pointer to table name */ jpayne@69: int *pnCol, /* OUT: Number of columns in table */ jpayne@69: int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ jpayne@69: int *pbIndirect /* OUT: True for an 'indirect' change */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain The Primary Key Definition Of A Table jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** For each modified table, a changeset includes the following: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • The number of columns in the table, and jpayne@69: **
  • Which of those columns make up the tables PRIMARY KEY. jpayne@69: **
jpayne@69: ** jpayne@69: ** This function is used to find which columns comprise the PRIMARY KEY of jpayne@69: ** the table modified by the change that iterator pIter currently points to. jpayne@69: ** If successful, *pabPK is set to point to an array of nCol entries, where jpayne@69: ** nCol is the number of columns in the table. Elements of *pabPK are set to jpayne@69: ** 0x01 if the corresponding column is part of the tables primary key, or jpayne@69: ** 0x00 if it is not. jpayne@69: ** jpayne@69: ** If argument pnCol is not NULL, then *pnCol is set to the number of columns jpayne@69: ** in the table. jpayne@69: ** jpayne@69: ** If this function is called when the iterator does not point to a valid jpayne@69: ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, jpayne@69: ** SQLITE_OK is returned and the output variables populated as described jpayne@69: ** above. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_pk( jpayne@69: sqlite3_changeset_iter *pIter, /* Iterator object */ jpayne@69: unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ jpayne@69: int *pnCol /* OUT: Number of entries in output array */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain old.* Values From A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** The pIter argument passed to this function may either be an iterator jpayne@69: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator jpayne@69: ** created by [sqlite3changeset_start()]. In the latter case, the most recent jpayne@69: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. jpayne@69: ** Furthermore, it may only be called if the type of change that the iterator jpayne@69: ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, jpayne@69: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. jpayne@69: ** jpayne@69: ** Argument iVal must be greater than or equal to 0, and less than the number jpayne@69: ** of columns in the table affected by the current change. Otherwise, jpayne@69: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. jpayne@69: ** jpayne@69: ** If successful, this function sets *ppValue to point to a protected jpayne@69: ** sqlite3_value object containing the iVal'th value from the vector of jpayne@69: ** original row values stored as part of the UPDATE or DELETE change and jpayne@69: ** returns SQLITE_OK. The name of the function comes from the fact that this jpayne@69: ** is similar to the "old.*" columns available to update or delete triggers. jpayne@69: ** jpayne@69: ** If some other error occurs (e.g. an OOM condition), an SQLite error code jpayne@69: ** is returned and *ppValue is set to NULL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_old( jpayne@69: sqlite3_changeset_iter *pIter, /* Changeset iterator */ jpayne@69: int iVal, /* Column number */ jpayne@69: sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain new.* Values From A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** The pIter argument passed to this function may either be an iterator jpayne@69: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator jpayne@69: ** created by [sqlite3changeset_start()]. In the latter case, the most recent jpayne@69: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. jpayne@69: ** Furthermore, it may only be called if the type of change that the iterator jpayne@69: ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, jpayne@69: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. jpayne@69: ** jpayne@69: ** Argument iVal must be greater than or equal to 0, and less than the number jpayne@69: ** of columns in the table affected by the current change. Otherwise, jpayne@69: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. jpayne@69: ** jpayne@69: ** If successful, this function sets *ppValue to point to a protected jpayne@69: ** sqlite3_value object containing the iVal'th value from the vector of jpayne@69: ** new row values stored as part of the UPDATE or INSERT change and jpayne@69: ** returns SQLITE_OK. If the change is an UPDATE and does not include jpayne@69: ** a new value for the requested column, *ppValue is set to NULL and jpayne@69: ** SQLITE_OK returned. The name of the function comes from the fact that jpayne@69: ** this is similar to the "new.*" columns available to update or delete jpayne@69: ** triggers. jpayne@69: ** jpayne@69: ** If some other error occurs (e.g. an OOM condition), an SQLite error code jpayne@69: ** is returned and *ppValue is set to NULL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_new( jpayne@69: sqlite3_changeset_iter *pIter, /* Changeset iterator */ jpayne@69: int iVal, /* Column number */ jpayne@69: sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** This function should only be used with iterator objects passed to a jpayne@69: ** conflict-handler callback by [sqlite3changeset_apply()] with either jpayne@69: ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function jpayne@69: ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue jpayne@69: ** is set to NULL. jpayne@69: ** jpayne@69: ** Argument iVal must be greater than or equal to 0, and less than the number jpayne@69: ** of columns in the table affected by the current change. Otherwise, jpayne@69: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. jpayne@69: ** jpayne@69: ** If successful, this function sets *ppValue to point to a protected jpayne@69: ** sqlite3_value object containing the iVal'th value from the jpayne@69: ** "conflicting row" associated with the current conflict-handler callback jpayne@69: ** and returns SQLITE_OK. jpayne@69: ** jpayne@69: ** If some other error occurs (e.g. an OOM condition), an SQLite error code jpayne@69: ** is returned and *ppValue is set to NULL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_conflict( jpayne@69: sqlite3_changeset_iter *pIter, /* Changeset iterator */ jpayne@69: int iVal, /* Column number */ jpayne@69: sqlite3_value **ppValue /* OUT: Value from conflicting row */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** This function may only be called with an iterator passed to an jpayne@69: ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case jpayne@69: ** it sets the output variable to the total number of known foreign key jpayne@69: ** violations in the destination database and returns SQLITE_OK. jpayne@69: ** jpayne@69: ** In all other cases this function returns SQLITE_MISUSE. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_fk_conflicts( jpayne@69: sqlite3_changeset_iter *pIter, /* Changeset iterator */ jpayne@69: int *pnOut /* OUT: Number of FK violations */ jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Finalize A Changeset Iterator jpayne@69: ** METHOD: sqlite3_changeset_iter jpayne@69: ** jpayne@69: ** This function is used to finalize an iterator allocated with jpayne@69: ** [sqlite3changeset_start()]. jpayne@69: ** jpayne@69: ** This function should only be called on iterators created using the jpayne@69: ** [sqlite3changeset_start()] function. If an application calls this jpayne@69: ** function with an iterator passed to a conflict-handler by jpayne@69: ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the jpayne@69: ** call has no effect. jpayne@69: ** jpayne@69: ** If an error was encountered within a call to an sqlite3changeset_xxx() jpayne@69: ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an jpayne@69: ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding jpayne@69: ** to that error is returned by this function. Otherwise, SQLITE_OK is jpayne@69: ** returned. This is to allow the following pattern (pseudo-code): jpayne@69: ** jpayne@69: ** 
jpayne@69: **   sqlite3changeset_start();
jpayne@69: **   while( SQLITE_ROW==sqlite3changeset_next() ){
jpayne@69: **     // Do something with change.
jpayne@69: **   }
jpayne@69: **   rc = sqlite3changeset_finalize();
jpayne@69: **   if( rc!=SQLITE_OK ){
jpayne@69: **     // An error has occurred
jpayne@69: **   }
jpayne@69: **
jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Invert A Changeset jpayne@69: ** jpayne@69: ** This function is used to "invert" a changeset object. Applying an inverted jpayne@69: ** changeset to a database reverses the effects of applying the uninverted jpayne@69: ** changeset. Specifically: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • Each DELETE change is changed to an INSERT, and jpayne@69: **
  • Each INSERT change is changed to a DELETE, and jpayne@69: **
  • For each UPDATE change, the old.* and new.* values are exchanged. jpayne@69: **
jpayne@69: ** jpayne@69: ** This function does not change the order in which changes appear within jpayne@69: ** the changeset. It merely reverses the sense of each individual change. jpayne@69: ** jpayne@69: ** If successful, a pointer to a buffer containing the inverted changeset jpayne@69: ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and jpayne@69: ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are jpayne@69: ** zeroed and an SQLite error code returned. jpayne@69: ** jpayne@69: ** It is the responsibility of the caller to eventually call sqlite3_free() jpayne@69: ** on the *ppOut pointer to free the buffer allocation following a successful jpayne@69: ** call to this function. jpayne@69: ** jpayne@69: ** WARNING/TODO: This function currently assumes that the input is a valid jpayne@69: ** changeset. If it is not, the results are undefined. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_invert( jpayne@69: int nIn, const void *pIn, /* Input changeset */ jpayne@69: int *pnOut, void **ppOut /* OUT: Inverse of input */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Concatenate Two Changeset Objects jpayne@69: ** jpayne@69: ** This function is used to concatenate two changesets, A and B, into a jpayne@69: ** single changeset. The result is a changeset equivalent to applying jpayne@69: ** changeset A followed by changeset B. jpayne@69: ** jpayne@69: ** This function combines the two input changesets using an jpayne@69: ** sqlite3_changegroup object. Calling it produces similar results as the jpayne@69: ** following code fragment: jpayne@69: ** jpayne@69: ** 
jpayne@69: **   sqlite3_changegroup *pGrp;
jpayne@69: **   rc = sqlite3_changegroup_new(&pGrp);
jpayne@69: **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
jpayne@69: **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
jpayne@69: **   if( rc==SQLITE_OK ){
jpayne@69: **     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
jpayne@69: **   }else{
jpayne@69: **     *ppOut = 0;
jpayne@69: **     *pnOut = 0;
jpayne@69: **   }
jpayne@69: **
jpayne@69: ** jpayne@69: ** Refer to the sqlite3_changegroup documentation below for details. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_concat( jpayne@69: int nA, /* Number of bytes in buffer pA */ jpayne@69: void *pA, /* Pointer to buffer containing changeset A */ jpayne@69: int nB, /* Number of bytes in buffer pB */ jpayne@69: void *pB, /* Pointer to buffer containing changeset B */ jpayne@69: int *pnOut, /* OUT: Number of bytes in output changeset */ jpayne@69: void **ppOut /* OUT: Buffer containing output changeset */ jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Upgrade the Schema of a Changeset/Patchset jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_upgrade( jpayne@69: sqlite3 *db, jpayne@69: const char *zDb, jpayne@69: int nIn, const void *pIn, /* Input changeset */ jpayne@69: int *pnOut, void **ppOut /* OUT: Inverse of input */ jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Changegroup Handle jpayne@69: ** jpayne@69: ** A changegroup is an object used to combine two or more jpayne@69: ** [changesets] or [patchsets] jpayne@69: */ jpayne@69: typedef struct sqlite3_changegroup sqlite3_changegroup; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create A New Changegroup Object jpayne@69: ** CONSTRUCTOR: sqlite3_changegroup jpayne@69: ** jpayne@69: ** An sqlite3_changegroup object is used to combine two or more changesets jpayne@69: ** (or patchsets) into a single changeset (or patchset). A single changegroup jpayne@69: ** object may combine changesets or patchsets, but not both. The output is jpayne@69: ** always in the same format as the input. jpayne@69: ** jpayne@69: ** If successful, this function returns SQLITE_OK and populates (*pp) with jpayne@69: ** a pointer to a new sqlite3_changegroup object before returning. The caller jpayne@69: ** should eventually free the returned object using a call to jpayne@69: ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code jpayne@69: ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. jpayne@69: ** jpayne@69: ** The usual usage pattern for an sqlite3_changegroup object is as follows: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • It is created using a call to sqlite3changegroup_new(). jpayne@69: ** jpayne@69: **
  • Zero or more changesets (or patchsets) are added to the object jpayne@69: ** by calling sqlite3changegroup_add(). jpayne@69: ** jpayne@69: **
  • The result of combining all input changesets together is obtained jpayne@69: ** by the application via a call to sqlite3changegroup_output(). jpayne@69: ** jpayne@69: **
  • The object is deleted using a call to sqlite3changegroup_delete(). jpayne@69: **
jpayne@69: ** jpayne@69: ** Any number of calls to add() and output() may be made between the calls to jpayne@69: ** new() and delete(), and in any order. jpayne@69: ** jpayne@69: ** As well as the regular sqlite3changegroup_add() and jpayne@69: ** sqlite3changegroup_output() functions, also available are the streaming jpayne@69: ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Add a Schema to a Changegroup jpayne@69: ** METHOD: sqlite3_changegroup_schema jpayne@69: ** jpayne@69: ** This method may be used to optionally enforce the rule that the changesets jpayne@69: ** added to the changegroup handle must match the schema of database zDb jpayne@69: ** ("main", "temp", or the name of an attached database). If jpayne@69: ** sqlite3changegroup_add() is called to add a changeset that is not compatible jpayne@69: ** with the configured schema, SQLITE_SCHEMA is returned and the changegroup jpayne@69: ** object is left in an undefined state. jpayne@69: ** jpayne@69: ** A changeset schema is considered compatible with the database schema in jpayne@69: ** the same way as for sqlite3changeset_apply(). Specifically, for each jpayne@69: ** table in the changeset, there exists a database table with: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • The name identified by the changeset, and jpayne@69: **
  • at least as many columns as recorded in the changeset, and jpayne@69: **
  • the primary key columns in the same position as recorded in jpayne@69: ** the changeset. jpayne@69: **
jpayne@69: ** jpayne@69: ** The output of the changegroup object always has the same schema as the jpayne@69: ** database nominated using this function. In cases where changesets passed jpayne@69: ** to sqlite3changegroup_add() have fewer columns than the corresponding table jpayne@69: ** in the database schema, these are filled in using the default column jpayne@69: ** values from the database schema. This makes it possible to combined jpayne@69: ** changesets that have different numbers of columns for a single table jpayne@69: ** within a changegroup, provided that they are otherwise compatible. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Add A Changeset To A Changegroup jpayne@69: ** METHOD: sqlite3_changegroup jpayne@69: ** jpayne@69: ** Add all changes within the changeset (or patchset) in buffer pData (size jpayne@69: ** nData bytes) to the changegroup. jpayne@69: ** jpayne@69: ** If the buffer contains a patchset, then all prior calls to this function jpayne@69: ** on the same changegroup object must also have specified patchsets. Or, if jpayne@69: ** the buffer contains a changeset, so must have the earlier calls to this jpayne@69: ** function. Otherwise, SQLITE_ERROR is returned and no changes are added jpayne@69: ** to the changegroup. jpayne@69: ** jpayne@69: ** Rows within the changeset and changegroup are identified by the values in jpayne@69: ** their PRIMARY KEY columns. A change in the changeset is considered to jpayne@69: ** apply to the same row as a change already present in the changegroup if jpayne@69: ** the two rows have the same primary key. jpayne@69: ** jpayne@69: ** Changes to rows that do not already appear in the changegroup are jpayne@69: ** simply copied into it. Or, if both the new changeset and the changegroup jpayne@69: ** contain changes that apply to a single row, the final contents of the jpayne@69: ** changegroup depends on the type of each change, as follows: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: **
Existing Change New Change Output Change jpayne@69: **
INSERT INSERT jpayne@69: ** The new change is ignored. This case does not occur if the new jpayne@69: ** changeset was recorded immediately after the changesets already jpayne@69: ** added to the changegroup. jpayne@69: **
INSERT UPDATE jpayne@69: ** The INSERT change remains in the changegroup. The values in the jpayne@69: ** INSERT change are modified as if the row was inserted by the jpayne@69: ** existing change and then updated according to the new change. jpayne@69: **
INSERT DELETE jpayne@69: ** The existing INSERT is removed from the changegroup. The DELETE is jpayne@69: ** not added. jpayne@69: **
UPDATE INSERT jpayne@69: ** The new change is ignored. This case does not occur if the new jpayne@69: ** changeset was recorded immediately after the changesets already jpayne@69: ** added to the changegroup. jpayne@69: **
UPDATE UPDATE jpayne@69: ** The existing UPDATE remains within the changegroup. It is amended jpayne@69: ** so that the accompanying values are as if the row was updated once jpayne@69: ** by the existing change and then again by the new change. jpayne@69: **
UPDATE DELETE jpayne@69: ** The existing UPDATE is replaced by the new DELETE within the jpayne@69: ** changegroup. jpayne@69: **
DELETE INSERT jpayne@69: ** If one or more of the column values in the row inserted by the jpayne@69: ** new change differ from those in the row deleted by the existing jpayne@69: ** change, the existing DELETE is replaced by an UPDATE within the jpayne@69: ** changegroup. Otherwise, if the inserted row is exactly the same jpayne@69: ** as the deleted row, the existing DELETE is simply discarded. jpayne@69: **
DELETE UPDATE jpayne@69: ** The new change is ignored. This case does not occur if the new jpayne@69: ** changeset was recorded immediately after the changesets already jpayne@69: ** added to the changegroup. jpayne@69: **
DELETE DELETE jpayne@69: ** The new change is ignored. This case does not occur if the new jpayne@69: ** changeset was recorded immediately after the changesets already jpayne@69: ** added to the changegroup. jpayne@69: **
jpayne@69: ** jpayne@69: ** If the new changeset contains changes to a table that is already present jpayne@69: ** in the changegroup, then the number of columns and the position of the jpayne@69: ** primary key columns for the table must be consistent. If this is not the jpayne@69: ** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup jpayne@69: ** object has been configured with a database schema using the jpayne@69: ** sqlite3changegroup_schema() API, then it is possible to combine changesets jpayne@69: ** with different numbers of columns for a single table, provided that jpayne@69: ** they are otherwise compatible. jpayne@69: ** jpayne@69: ** If the input changeset appears to be corrupt and the corruption is jpayne@69: ** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition jpayne@69: ** occurs during processing, this function returns SQLITE_NOMEM. jpayne@69: ** jpayne@69: ** In all cases, if an error occurs the state of the final contents of the jpayne@69: ** changegroup is undefined. If no error occurs, SQLITE_OK is returned. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Add A Single Change To A Changegroup jpayne@69: ** METHOD: sqlite3_changegroup jpayne@69: ** jpayne@69: ** This function adds the single change currently indicated by the iterator jpayne@69: ** passed as the second argument to the changegroup object. The rules for jpayne@69: ** adding the change are just as described for [sqlite3changegroup_add()]. jpayne@69: ** jpayne@69: ** If the change is successfully added to the changegroup, SQLITE_OK is jpayne@69: ** returned. Otherwise, an SQLite error code is returned. jpayne@69: ** jpayne@69: ** The iterator must point to a valid entry when this function is called. jpayne@69: ** If it does not, SQLITE_ERROR is returned and no change is added to the jpayne@69: ** changegroup. Additionally, the iterator must not have been opened with jpayne@69: ** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also jpayne@69: ** returned. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changegroup_add_change( jpayne@69: sqlite3_changegroup*, jpayne@69: sqlite3_changeset_iter* jpayne@69: ); jpayne@69: jpayne@69: jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Obtain A Composite Changeset From A Changegroup jpayne@69: ** METHOD: sqlite3_changegroup jpayne@69: ** jpayne@69: ** Obtain a buffer containing a changeset (or patchset) representing the jpayne@69: ** current contents of the changegroup. If the inputs to the changegroup jpayne@69: ** were themselves changesets, the output is a changeset. Or, if the jpayne@69: ** inputs were patchsets, the output is also a patchset. jpayne@69: ** jpayne@69: ** As with the output of the sqlite3session_changeset() and jpayne@69: ** sqlite3session_patchset() functions, all changes related to a single jpayne@69: ** table are grouped together in the output of this function. Tables appear jpayne@69: ** in the same order as for the very first changeset added to the changegroup. jpayne@69: ** If the second or subsequent changesets added to the changegroup contain jpayne@69: ** changes for tables that do not appear in the first changeset, they are jpayne@69: ** appended onto the end of the output changeset, again in the order in jpayne@69: ** which they are first encountered. jpayne@69: ** jpayne@69: ** If an error occurs, an SQLite error code is returned and the output jpayne@69: ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK jpayne@69: ** is returned and the output variables are set to the size of and a jpayne@69: ** pointer to the output buffer, respectively. In this case it is the jpayne@69: ** responsibility of the caller to eventually free the buffer using a jpayne@69: ** call to sqlite3_free(). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changegroup_output( jpayne@69: sqlite3_changegroup*, jpayne@69: int *pnData, /* OUT: Size of output buffer in bytes */ jpayne@69: void **ppData /* OUT: Pointer to output buffer */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Delete A Changegroup Object jpayne@69: ** DESTRUCTOR: sqlite3_changegroup jpayne@69: */ jpayne@69: SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Apply A Changeset To A Database jpayne@69: ** jpayne@69: ** Apply a changeset or patchset to a database. These functions attempt to jpayne@69: ** update the "main" database attached to handle db with the changes found in jpayne@69: ** the changeset passed via the second and third arguments. jpayne@69: ** jpayne@69: ** The fourth argument (xFilter) passed to these functions is the "filter jpayne@69: ** callback". If it is not NULL, then for each table affected by at least one jpayne@69: ** change in the changeset, the filter callback is invoked with jpayne@69: ** the table name as the second argument, and a copy of the context pointer jpayne@69: ** passed as the sixth argument as the first. If the "filter callback" jpayne@69: ** returns zero, then no attempt is made to apply any changes to the table. jpayne@69: ** Otherwise, if the return value is non-zero or the xFilter argument to jpayne@69: ** is NULL, all changes related to the table are attempted. jpayne@69: ** jpayne@69: ** For each table that is not excluded by the filter callback, this function jpayne@69: ** tests that the target database contains a compatible table. A table is jpayne@69: ** considered compatible if all of the following are true: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • The table has the same name as the name recorded in the jpayne@69: ** changeset, and jpayne@69: **
  • The table has at least as many columns as recorded in the jpayne@69: ** changeset, and jpayne@69: **
  • The table has primary key columns in the same position as jpayne@69: ** recorded in the changeset. jpayne@69: **
jpayne@69: ** jpayne@69: ** If there is no compatible table, it is not an error, but none of the jpayne@69: ** changes associated with the table are applied. A warning message is issued jpayne@69: ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most jpayne@69: ** one such warning is issued for each table in the changeset. jpayne@69: ** jpayne@69: ** For each change for which there is a compatible table, an attempt is made jpayne@69: ** to modify the table contents according to the UPDATE, INSERT or DELETE jpayne@69: ** change. If a change cannot be applied cleanly, the conflict handler jpayne@69: ** function passed as the fifth argument to sqlite3changeset_apply() may be jpayne@69: ** invoked. A description of exactly when the conflict handler is invoked for jpayne@69: ** each type of change is below. jpayne@69: ** jpayne@69: ** Unlike the xFilter argument, xConflict may not be passed NULL. The results jpayne@69: ** of passing anything other than a valid function pointer as the xConflict jpayne@69: ** argument are undefined. jpayne@69: ** jpayne@69: ** Each time the conflict handler function is invoked, it must return one jpayne@69: ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or jpayne@69: ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned jpayne@69: ** if the second argument passed to the conflict handler is either jpayne@69: ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler jpayne@69: ** returns an illegal value, any changes already made are rolled back and jpayne@69: ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different jpayne@69: ** actions are taken by sqlite3changeset_apply() depending on the value jpayne@69: ** returned by each invocation of the conflict-handler function. Refer to jpayne@69: ** the documentation for the three jpayne@69: ** [SQLITE_CHANGESET_OMIT|available return values] for details. jpayne@69: ** jpayne@69: **
jpayne@69: **
DELETE Changes
jpayne@69: ** For each DELETE change, the function checks if the target database jpayne@69: ** contains a row with the same primary key value (or values) as the jpayne@69: ** original row values stored in the changeset. If it does, and the values jpayne@69: ** stored in all non-primary key columns also match the values stored in jpayne@69: ** the changeset the row is deleted from the target database. jpayne@69: ** jpayne@69: ** If a row with matching primary key values is found, but one or more of jpayne@69: ** the non-primary key fields contains a value different from the original jpayne@69: ** row value stored in the changeset, the conflict-handler function is jpayne@69: ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the jpayne@69: ** database table has more columns than are recorded in the changeset, jpayne@69: ** only the values of those non-primary key fields are compared against jpayne@69: ** the current database contents - any trailing database table columns jpayne@69: ** are ignored. jpayne@69: ** jpayne@69: ** If no row with matching primary key values is found in the database, jpayne@69: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] jpayne@69: ** passed as the second argument. jpayne@69: ** jpayne@69: ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT jpayne@69: ** (which can only happen if a foreign key constraint is violated), the jpayne@69: ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] jpayne@69: ** passed as the second argument. This includes the case where the DELETE jpayne@69: ** operation is attempted because an earlier call to the conflict handler jpayne@69: ** function returned [SQLITE_CHANGESET_REPLACE]. jpayne@69: ** jpayne@69: **
INSERT Changes
jpayne@69: ** For each INSERT change, an attempt is made to insert the new row into jpayne@69: ** the database. If the changeset row contains fewer fields than the jpayne@69: ** database table, the trailing fields are populated with their default jpayne@69: ** values. jpayne@69: ** jpayne@69: ** If the attempt to insert the row fails because the database already jpayne@69: ** contains a row with the same primary key values, the conflict handler jpayne@69: ** function is invoked with the second argument set to jpayne@69: ** [SQLITE_CHANGESET_CONFLICT]. jpayne@69: ** jpayne@69: ** If the attempt to insert the row fails because of some other constraint jpayne@69: ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is jpayne@69: ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. jpayne@69: ** This includes the case where the INSERT operation is re-attempted because jpayne@69: ** an earlier call to the conflict handler function returned jpayne@69: ** [SQLITE_CHANGESET_REPLACE]. jpayne@69: ** jpayne@69: **
UPDATE Changes
jpayne@69: ** For each UPDATE change, the function checks if the target database jpayne@69: ** contains a row with the same primary key value (or values) as the jpayne@69: ** original row values stored in the changeset. If it does, and the values jpayne@69: ** stored in all modified non-primary key columns also match the values jpayne@69: ** stored in the changeset the row is updated within the target database. jpayne@69: ** jpayne@69: ** If a row with matching primary key values is found, but one or more of jpayne@69: ** the modified non-primary key fields contains a value different from an jpayne@69: ** original row value stored in the changeset, the conflict-handler function jpayne@69: ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since jpayne@69: ** UPDATE changes only contain values for non-primary key fields that are jpayne@69: ** to be modified, only those fields need to match the original values to jpayne@69: ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. jpayne@69: ** jpayne@69: ** If no row with matching primary key values is found in the database, jpayne@69: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] jpayne@69: ** passed as the second argument. jpayne@69: ** jpayne@69: ** If the UPDATE operation is attempted, but SQLite returns jpayne@69: ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with jpayne@69: ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. jpayne@69: ** This includes the case where the UPDATE operation is attempted after jpayne@69: ** an earlier call to the conflict handler function returned jpayne@69: ** [SQLITE_CHANGESET_REPLACE]. jpayne@69: **
jpayne@69: ** jpayne@69: ** It is safe to execute SQL statements, including those that write to the jpayne@69: ** table that the callback related to, from within the xConflict callback. jpayne@69: ** This can be used to further customize the application's conflict jpayne@69: ** resolution strategy. jpayne@69: ** jpayne@69: ** All changes made by these functions are enclosed in a savepoint transaction. jpayne@69: ** If any other error (aside from a constraint failure when attempting to jpayne@69: ** write to the target database) occurs, then the savepoint transaction is jpayne@69: ** rolled back, restoring the target database to its original state, and an jpayne@69: ** SQLite error code returned. jpayne@69: ** jpayne@69: ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and jpayne@69: ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() jpayne@69: ** may set (*ppRebase) to point to a "rebase" that may be used with the jpayne@69: ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) jpayne@69: ** is set to the size of the buffer in bytes. It is the responsibility of the jpayne@69: ** caller to eventually free any such buffer using sqlite3_free(). The buffer jpayne@69: ** is only allocated and populated if one or more conflicts were encountered jpayne@69: ** while applying the patchset. See comments surrounding the sqlite3_rebaser jpayne@69: ** APIs for further details. jpayne@69: ** jpayne@69: ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent jpayne@69: ** may be modified by passing a combination of jpayne@69: ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. jpayne@69: ** jpayne@69: ** Note that the sqlite3changeset_apply_v2() API is still experimental jpayne@69: ** and therefore subject to change. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_apply( jpayne@69: sqlite3 *db, /* Apply change to "main" db of this handle */ jpayne@69: int nChangeset, /* Size of changeset in bytes */ jpayne@69: void *pChangeset, /* Changeset blob */ jpayne@69: int(*xFilter)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ), jpayne@69: int(*xConflict)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ jpayne@69: sqlite3_changeset_iter *p /* Handle describing change and conflict */ jpayne@69: ), jpayne@69: void *pCtx /* First argument passed to xConflict */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_apply_v2( jpayne@69: sqlite3 *db, /* Apply change to "main" db of this handle */ jpayne@69: int nChangeset, /* Size of changeset in bytes */ jpayne@69: void *pChangeset, /* Changeset blob */ jpayne@69: int(*xFilter)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ), jpayne@69: int(*xConflict)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ jpayne@69: sqlite3_changeset_iter *p /* Handle describing change and conflict */ jpayne@69: ), jpayne@69: void *pCtx, /* First argument passed to xConflict */ jpayne@69: void **ppRebase, int *pnRebase, /* OUT: Rebase data */ jpayne@69: int flags /* SESSION_CHANGESETAPPLY_* flags */ jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Flags for sqlite3changeset_apply_v2 jpayne@69: ** jpayne@69: ** The following flags may passed via the 9th parameter to jpayne@69: ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: jpayne@69: ** jpayne@69: **
jpayne@69: **
SQLITE_CHANGESETAPPLY_NOSAVEPOINT
jpayne@69: ** Usually, the sessions module encloses all operations performed by jpayne@69: ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The jpayne@69: ** SAVEPOINT is committed if the changeset or patchset is successfully jpayne@69: ** applied, or rolled back if an error occurs. Specifying this flag jpayne@69: ** causes the sessions module to omit this savepoint. In this case, if the jpayne@69: ** caller has an open transaction or savepoint when apply_v2() is called, jpayne@69: ** it may revert the partially applied changeset by rolling it back. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESETAPPLY_INVERT
jpayne@69: ** Invert the changeset before applying it. This is equivalent to inverting jpayne@69: ** a changeset using sqlite3changeset_invert() before applying it. It is jpayne@69: ** an error to specify this flag with a patchset. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESETAPPLY_IGNORENOOP
jpayne@69: ** Do not invoke the conflict handler callback for any changes that jpayne@69: ** would not actually modify the database even if they were applied. jpayne@69: ** Specifically, this means that the conflict handler is not invoked jpayne@69: ** for: jpayne@69: **
    jpayne@69: **
  • a delete change if the row being deleted cannot be found, jpayne@69: **
  • an update change if the modified fields are already set to jpayne@69: ** their new values in the conflicting row, or jpayne@69: **
  • an insert change if all fields of the conflicting row match jpayne@69: ** the row being inserted. jpayne@69: **
jpayne@69: ** jpayne@69: **
SQLITE_CHANGESETAPPLY_FKNOACTION
jpayne@69: ** If this flag it set, then all foreign key constraints in the target jpayne@69: ** database behave as if they were declared with "ON UPDATE NO ACTION ON jpayne@69: ** DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL jpayne@69: ** or SET DEFAULT. jpayne@69: */ jpayne@69: #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 jpayne@69: #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 jpayne@69: #define SQLITE_CHANGESETAPPLY_IGNORENOOP 0x0004 jpayne@69: #define SQLITE_CHANGESETAPPLY_FKNOACTION 0x0008 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Constants Passed To The Conflict Handler jpayne@69: ** jpayne@69: ** Values that may be passed as the second argument to a conflict-handler. jpayne@69: ** jpayne@69: **
jpayne@69: **
SQLITE_CHANGESET_DATA
jpayne@69: ** The conflict handler is invoked with CHANGESET_DATA as the second argument jpayne@69: ** when processing a DELETE or UPDATE change if a row with the required jpayne@69: ** PRIMARY KEY fields is present in the database, but one or more other jpayne@69: ** (non primary-key) fields modified by the update do not contain the jpayne@69: ** expected "before" values. jpayne@69: ** jpayne@69: ** The conflicting row, in this case, is the database row with the matching jpayne@69: ** primary key. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_NOTFOUND
jpayne@69: ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second jpayne@69: ** argument when processing a DELETE or UPDATE change if a row with the jpayne@69: ** required PRIMARY KEY fields is not present in the database. jpayne@69: ** jpayne@69: ** There is no conflicting row in this case. The results of invoking the jpayne@69: ** sqlite3changeset_conflict() API are undefined. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_CONFLICT
jpayne@69: ** CHANGESET_CONFLICT is passed as the second argument to the conflict jpayne@69: ** handler while processing an INSERT change if the operation would result jpayne@69: ** in duplicate primary key values. jpayne@69: ** jpayne@69: ** The conflicting row in this case is the database row with the matching jpayne@69: ** primary key. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_FOREIGN_KEY
jpayne@69: ** If foreign key handling is enabled, and applying a changeset leaves the jpayne@69: ** database in a state containing foreign key violations, the conflict jpayne@69: ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument jpayne@69: ** exactly once before the changeset is committed. If the conflict handler jpayne@69: ** returns CHANGESET_OMIT, the changes, including those that caused the jpayne@69: ** foreign key constraint violation, are committed. Or, if it returns jpayne@69: ** CHANGESET_ABORT, the changeset is rolled back. jpayne@69: ** jpayne@69: ** No current or conflicting row information is provided. The only function jpayne@69: ** it is possible to call on the supplied sqlite3_changeset_iter handle jpayne@69: ** is sqlite3changeset_fk_conflicts(). jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_CONSTRAINT
jpayne@69: ** If any other constraint violation occurs while applying a change (i.e. jpayne@69: ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is jpayne@69: ** invoked with CHANGESET_CONSTRAINT as the second argument. jpayne@69: ** jpayne@69: ** There is no conflicting row in this case. The results of invoking the jpayne@69: ** sqlite3changeset_conflict() API are undefined. jpayne@69: ** jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_CHANGESET_DATA 1 jpayne@69: #define SQLITE_CHANGESET_NOTFOUND 2 jpayne@69: #define SQLITE_CHANGESET_CONFLICT 3 jpayne@69: #define SQLITE_CHANGESET_CONSTRAINT 4 jpayne@69: #define SQLITE_CHANGESET_FOREIGN_KEY 5 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Constants Returned By The Conflict Handler jpayne@69: ** jpayne@69: ** A conflict handler callback must return one of the following three values. jpayne@69: ** jpayne@69: **
jpayne@69: **
SQLITE_CHANGESET_OMIT
jpayne@69: ** If a conflict handler returns this value no special action is taken. The jpayne@69: ** change that caused the conflict is not applied. The session module jpayne@69: ** continues to the next change in the changeset. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_REPLACE
jpayne@69: ** This value may only be returned if the second argument to the conflict jpayne@69: ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this jpayne@69: ** is not the case, any changes applied so far are rolled back and the jpayne@69: ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. jpayne@69: ** jpayne@69: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict jpayne@69: ** handler, then the conflicting row is either updated or deleted, depending jpayne@69: ** on the type of change. jpayne@69: ** jpayne@69: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict jpayne@69: ** handler, then the conflicting row is removed from the database and a jpayne@69: ** second attempt to apply the change is made. If this second attempt fails, jpayne@69: ** the original row is restored to the database before continuing. jpayne@69: ** jpayne@69: **
SQLITE_CHANGESET_ABORT
jpayne@69: ** If this value is returned, any changes applied so far are rolled back jpayne@69: ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. jpayne@69: **
jpayne@69: */ jpayne@69: #define SQLITE_CHANGESET_OMIT 0 jpayne@69: #define SQLITE_CHANGESET_REPLACE 1 jpayne@69: #define SQLITE_CHANGESET_ABORT 2 jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Rebasing changesets jpayne@69: ** EXPERIMENTAL jpayne@69: ** jpayne@69: ** Suppose there is a site hosting a database in state S0. And that jpayne@69: ** modifications are made that move that database to state S1 and a jpayne@69: ** changeset recorded (the "local" changeset). Then, a changeset based jpayne@69: ** on S0 is received from another site (the "remote" changeset) and jpayne@69: ** applied to the database. The database is then in state jpayne@69: ** (S1+"remote"), where the exact state depends on any conflict jpayne@69: ** resolution decisions (OMIT or REPLACE) made while applying "remote". jpayne@69: ** Rebasing a changeset is to update it to take those conflict jpayne@69: ** resolution decisions into account, so that the same conflicts jpayne@69: ** do not have to be resolved elsewhere in the network. jpayne@69: ** jpayne@69: ** For example, if both the local and remote changesets contain an jpayne@69: ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": jpayne@69: ** jpayne@69: ** local: INSERT INTO t1 VALUES(1, 'v1'); jpayne@69: ** remote: INSERT INTO t1 VALUES(1, 'v2'); jpayne@69: ** jpayne@69: ** and the conflict resolution is REPLACE, then the INSERT change is jpayne@69: ** removed from the local changeset (it was overridden). Or, if the jpayne@69: ** conflict resolution was "OMIT", then the local changeset is modified jpayne@69: ** to instead contain: jpayne@69: ** jpayne@69: ** UPDATE t1 SET b = 'v2' WHERE a=1; jpayne@69: ** jpayne@69: ** Changes within the local changeset are rebased as follows: jpayne@69: ** jpayne@69: **
jpayne@69: **
Local INSERT
jpayne@69: ** This may only conflict with a remote INSERT. If the conflict jpayne@69: ** resolution was OMIT, then add an UPDATE change to the rebased jpayne@69: ** changeset. Or, if the conflict resolution was REPLACE, add jpayne@69: ** nothing to the rebased changeset. jpayne@69: ** jpayne@69: **
Local DELETE
jpayne@69: ** This may conflict with a remote UPDATE or DELETE. In both cases the jpayne@69: ** only possible resolution is OMIT. If the remote operation was a jpayne@69: ** DELETE, then add no change to the rebased changeset. If the remote jpayne@69: ** operation was an UPDATE, then the old.* fields of change are updated jpayne@69: ** to reflect the new.* values in the UPDATE. jpayne@69: ** jpayne@69: **
Local UPDATE
jpayne@69: ** This may conflict with a remote UPDATE or DELETE. If it conflicts jpayne@69: ** with a DELETE, and the conflict resolution was OMIT, then the update jpayne@69: ** is changed into an INSERT. Any undefined values in the new.* record jpayne@69: ** from the update change are filled in using the old.* values from jpayne@69: ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, jpayne@69: ** the UPDATE change is simply omitted from the rebased changeset. jpayne@69: ** jpayne@69: ** If conflict is with a remote UPDATE and the resolution is OMIT, then jpayne@69: ** the old.* values are rebased using the new.* values in the remote jpayne@69: ** change. Or, if the resolution is REPLACE, then the change is copied jpayne@69: ** into the rebased changeset with updates to columns also updated by jpayne@69: ** the conflicting remote UPDATE removed. If this means no columns would jpayne@69: ** be updated, the change is omitted. jpayne@69: **
jpayne@69: ** jpayne@69: ** A local change may be rebased against multiple remote changes jpayne@69: ** simultaneously. If a single key is modified by multiple remote jpayne@69: ** changesets, they are combined as follows before the local changeset jpayne@69: ** is rebased: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  • If there has been one or more REPLACE resolutions on a jpayne@69: ** key, it is rebased according to a REPLACE. jpayne@69: ** jpayne@69: **
  • If there have been no REPLACE resolutions on a key, then jpayne@69: ** the local changeset is rebased according to the most recent jpayne@69: ** of the OMIT resolutions. jpayne@69: **
jpayne@69: ** jpayne@69: ** Note that conflict resolutions from multiple remote changesets are jpayne@69: ** combined on a per-field basis, not per-row. This means that in the jpayne@69: ** case of multiple remote UPDATE operations, some fields of a single jpayne@69: ** local change may be rebased for REPLACE while others are rebased for jpayne@69: ** OMIT. jpayne@69: ** jpayne@69: ** In order to rebase a local changeset, the remote changeset must first jpayne@69: ** be applied to the local database using sqlite3changeset_apply_v2() and jpayne@69: ** the buffer of rebase information captured. Then: jpayne@69: ** jpayne@69: **
    jpayne@69: **
  1. An sqlite3_rebaser object is created by calling jpayne@69: ** sqlite3rebaser_create(). jpayne@69: **
  2. The new object is configured with the rebase buffer obtained from jpayne@69: ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). jpayne@69: ** If the local changeset is to be rebased against multiple remote jpayne@69: ** changesets, then sqlite3rebaser_configure() should be called jpayne@69: ** multiple times, in the same order that the multiple jpayne@69: ** sqlite3changeset_apply_v2() calls were made. jpayne@69: **
  3. Each local changeset is rebased by calling sqlite3rebaser_rebase(). jpayne@69: **
  4. The sqlite3_rebaser object is deleted by calling jpayne@69: ** sqlite3rebaser_delete(). jpayne@69: **
jpayne@69: */ jpayne@69: typedef struct sqlite3_rebaser sqlite3_rebaser; jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Create a changeset rebaser object. jpayne@69: ** EXPERIMENTAL jpayne@69: ** jpayne@69: ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to jpayne@69: ** point to the new object and return SQLITE_OK. Otherwise, if an error jpayne@69: ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) jpayne@69: ** to NULL. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configure a changeset rebaser object. jpayne@69: ** EXPERIMENTAL jpayne@69: ** jpayne@69: ** Configure the changeset rebaser object to rebase changesets according jpayne@69: ** to the conflict resolutions described by buffer pRebase (size nRebase jpayne@69: ** bytes), which must have been obtained from a previous call to jpayne@69: ** sqlite3changeset_apply_v2(). jpayne@69: */ jpayne@69: SQLITE_API int sqlite3rebaser_configure( jpayne@69: sqlite3_rebaser*, jpayne@69: int nRebase, const void *pRebase jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Rebase a changeset jpayne@69: ** EXPERIMENTAL jpayne@69: ** jpayne@69: ** Argument pIn must point to a buffer containing a changeset nIn bytes jpayne@69: ** in size. This function allocates and populates a buffer with a copy jpayne@69: ** of the changeset rebased according to the configuration of the jpayne@69: ** rebaser object passed as the first argument. If successful, (*ppOut) jpayne@69: ** is set to point to the new buffer containing the rebased changeset and jpayne@69: ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the jpayne@69: ** responsibility of the caller to eventually free the new buffer using jpayne@69: ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) jpayne@69: ** are set to zero and an SQLite error code returned. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3rebaser_rebase( jpayne@69: sqlite3_rebaser*, jpayne@69: int nIn, const void *pIn, jpayne@69: int *pnOut, void **ppOut jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Delete a changeset rebaser object. jpayne@69: ** EXPERIMENTAL jpayne@69: ** jpayne@69: ** Delete the changeset rebaser object and all associated resources. There jpayne@69: ** should be one call to this function for each successful invocation jpayne@69: ** of sqlite3rebaser_create(). jpayne@69: */ jpayne@69: SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Streaming Versions of API functions. jpayne@69: ** jpayne@69: ** The six streaming API xxx_strm() functions serve similar purposes to the jpayne@69: ** corresponding non-streaming API functions: jpayne@69: ** jpayne@69: ** jpayne@69: ** jpayne@69: **
Streaming functionNon-streaming equivalent
sqlite3changeset_apply_strm[sqlite3changeset_apply] jpayne@69: **
sqlite3changeset_apply_strm_v2[sqlite3changeset_apply_v2] jpayne@69: **
sqlite3changeset_concat_strm[sqlite3changeset_concat] jpayne@69: **
sqlite3changeset_invert_strm[sqlite3changeset_invert] jpayne@69: **
sqlite3changeset_start_strm[sqlite3changeset_start] jpayne@69: **
sqlite3session_changeset_strm[sqlite3session_changeset] jpayne@69: **
sqlite3session_patchset_strm[sqlite3session_patchset] jpayne@69: **
jpayne@69: ** jpayne@69: ** Non-streaming functions that accept changesets (or patchsets) as input jpayne@69: ** require that the entire changeset be stored in a single buffer in memory. jpayne@69: ** Similarly, those that return a changeset or patchset do so by returning jpayne@69: ** a pointer to a single large buffer allocated using sqlite3_malloc(). jpayne@69: ** Normally this is convenient. However, if an application running in a jpayne@69: ** low-memory environment is required to handle very large changesets, the jpayne@69: ** large contiguous memory allocations required can become onerous. jpayne@69: ** jpayne@69: ** In order to avoid this problem, instead of a single large buffer, input jpayne@69: ** is passed to a streaming API functions by way of a callback function that jpayne@69: ** the sessions module invokes to incrementally request input data as it is jpayne@69: ** required. In all cases, a pair of API function parameters such as jpayne@69: ** jpayne@69: ** 
jpayne@69: **        int nChangeset,
jpayne@69: **        void *pChangeset,
jpayne@69: **
jpayne@69: ** jpayne@69: ** Is replaced by: jpayne@69: ** jpayne@69: ** 
jpayne@69: **        int (*xInput)(void *pIn, void *pData, int *pnData),
jpayne@69: **        void *pIn,
jpayne@69: **
jpayne@69: ** jpayne@69: ** Each time the xInput callback is invoked by the sessions module, the first jpayne@69: ** argument passed is a copy of the supplied pIn context pointer. The second jpayne@69: ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no jpayne@69: ** error occurs the xInput method should copy up to (*pnData) bytes of data jpayne@69: ** into the buffer and set (*pnData) to the actual number of bytes copied jpayne@69: ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) jpayne@69: ** should be set to zero to indicate this. Or, if an error occurs, an SQLite jpayne@69: ** error code should be returned. In all cases, if an xInput callback returns jpayne@69: ** an error, all processing is abandoned and the streaming API function jpayne@69: ** returns a copy of the error code to the caller. jpayne@69: ** jpayne@69: ** In the case of sqlite3changeset_start_strm(), the xInput callback may be jpayne@69: ** invoked by the sessions module at any point during the lifetime of the jpayne@69: ** iterator. If such an xInput callback returns an error, the iterator enters jpayne@69: ** an error state, whereby all subsequent calls to iterator functions jpayne@69: ** immediately fail with the same error code as returned by xInput. jpayne@69: ** jpayne@69: ** Similarly, streaming API functions that return changesets (or patchsets) jpayne@69: ** return them in chunks by way of a callback function instead of via a jpayne@69: ** pointer to a single large buffer. In this case, a pair of parameters such jpayne@69: ** as: jpayne@69: ** jpayne@69: ** 
jpayne@69: **        int *pnChangeset,
jpayne@69: **        void **ppChangeset,
jpayne@69: **
jpayne@69: ** jpayne@69: ** Is replaced by: jpayne@69: ** jpayne@69: ** 
jpayne@69: **        int (*xOutput)(void *pOut, const void *pData, int nData),
jpayne@69: **        void *pOut
jpayne@69: **
jpayne@69: ** jpayne@69: ** The xOutput callback is invoked zero or more times to return data to jpayne@69: ** the application. The first parameter passed to each call is a copy of the jpayne@69: ** pOut pointer supplied by the application. The second parameter, pData, jpayne@69: ** points to a buffer nData bytes in size containing the chunk of output jpayne@69: ** data being returned. If the xOutput callback successfully processes the jpayne@69: ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, jpayne@69: ** it should return some other SQLite error code. In this case processing jpayne@69: ** is immediately abandoned and the streaming API function returns a copy jpayne@69: ** of the xOutput error code to the application. jpayne@69: ** jpayne@69: ** The sessions module never invokes an xOutput callback with the third jpayne@69: ** parameter set to a value less than or equal to zero. Other than this, jpayne@69: ** no guarantees are made as to the size of the chunks of data returned. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3changeset_apply_strm( jpayne@69: sqlite3 *db, /* Apply change to "main" db of this handle */ jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ jpayne@69: void *pIn, /* First arg for xInput */ jpayne@69: int(*xFilter)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ), jpayne@69: int(*xConflict)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ jpayne@69: sqlite3_changeset_iter *p /* Handle describing change and conflict */ jpayne@69: ), jpayne@69: void *pCtx /* First argument passed to xConflict */ jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_apply_v2_strm( jpayne@69: sqlite3 *db, /* Apply change to "main" db of this handle */ jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ jpayne@69: void *pIn, /* First arg for xInput */ jpayne@69: int(*xFilter)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: const char *zTab /* Table name */ jpayne@69: ), jpayne@69: int(*xConflict)( jpayne@69: void *pCtx, /* Copy of sixth arg to _apply() */ jpayne@69: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ jpayne@69: sqlite3_changeset_iter *p /* Handle describing change and conflict */ jpayne@69: ), jpayne@69: void *pCtx, /* First argument passed to xConflict */ jpayne@69: void **ppRebase, int *pnRebase, jpayne@69: int flags jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_concat_strm( jpayne@69: int (*xInputA)(void *pIn, void *pData, int *pnData), jpayne@69: void *pInA, jpayne@69: int (*xInputB)(void *pIn, void *pData, int *pnData), jpayne@69: void *pInB, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_invert_strm( jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), jpayne@69: void *pIn, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_start_strm( jpayne@69: sqlite3_changeset_iter **pp, jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), jpayne@69: void *pIn jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changeset_start_v2_strm( jpayne@69: sqlite3_changeset_iter **pp, jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), jpayne@69: void *pIn, jpayne@69: int flags jpayne@69: ); jpayne@69: SQLITE_API int sqlite3session_changeset_strm( jpayne@69: sqlite3_session *pSession, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: SQLITE_API int sqlite3session_patchset_strm( jpayne@69: sqlite3_session *pSession, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), jpayne@69: void *pIn jpayne@69: ); jpayne@69: SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: SQLITE_API int sqlite3rebaser_rebase_strm( jpayne@69: sqlite3_rebaser *pRebaser, jpayne@69: int (*xInput)(void *pIn, void *pData, int *pnData), jpayne@69: void *pIn, jpayne@69: int (*xOutput)(void *pOut, const void *pData, int nData), jpayne@69: void *pOut jpayne@69: ); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Configure global parameters jpayne@69: ** jpayne@69: ** The sqlite3session_config() interface is used to make global configuration jpayne@69: ** changes to the sessions module in order to tune it to the specific needs jpayne@69: ** of the application. jpayne@69: ** jpayne@69: ** The sqlite3session_config() interface is not threadsafe. If it is invoked jpayne@69: ** while any other thread is inside any other sessions method then the jpayne@69: ** results are undefined. Furthermore, if it is invoked after any sessions jpayne@69: ** related objects have been created, the results are also undefined. jpayne@69: ** jpayne@69: ** The first argument to the sqlite3session_config() function must be one jpayne@69: ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The jpayne@69: ** interpretation of the (void*) value passed as the second parameter and jpayne@69: ** the effect of calling this function depends on the value of the first jpayne@69: ** parameter. jpayne@69: ** jpayne@69: **
jpayne@69: **
SQLITE_SESSION_CONFIG_STRMSIZE
jpayne@69: ** By default, the sessions module streaming interfaces attempt to input jpayne@69: ** and output data in approximately 1 KiB chunks. This operand may be used jpayne@69: ** to set and query the value of this configuration setting. The pointer jpayne@69: ** passed as the second argument must point to a value of type (int). jpayne@69: ** If this value is greater than 0, it is used as the new streaming data jpayne@69: ** chunk size for both input and output. Before returning, the (int) value jpayne@69: ** pointed to by pArg is set to the final value of the streaming interface jpayne@69: ** chunk size. jpayne@69: **
jpayne@69: ** jpayne@69: ** This function returns SQLITE_OK if successful, or an SQLite error code jpayne@69: ** otherwise. jpayne@69: */ jpayne@69: SQLITE_API int sqlite3session_config(int op, void *pArg); jpayne@69: jpayne@69: /* jpayne@69: ** CAPI3REF: Values for sqlite3session_config(). jpayne@69: */ jpayne@69: #define SQLITE_SESSION_CONFIG_STRMSIZE 1 jpayne@69: jpayne@69: /* jpayne@69: ** Make sure we can call this stuff from C++. jpayne@69: */ jpayne@69: #ifdef __cplusplus jpayne@69: } jpayne@69: #endif jpayne@69: jpayne@69: #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ jpayne@69: jpayne@69: /******** End of sqlite3session.h *********/ jpayne@69: /******** Begin file fts5.h *********/ jpayne@69: /* jpayne@69: ** 2014 May 31 jpayne@69: ** jpayne@69: ** The author disclaims copyright to this source code. In place of jpayne@69: ** a legal notice, here is a blessing: jpayne@69: ** jpayne@69: ** May you do good and not evil. jpayne@69: ** May you find forgiveness for yourself and forgive others. jpayne@69: ** May you share freely, never taking more than you give. jpayne@69: ** jpayne@69: ****************************************************************************** jpayne@69: ** jpayne@69: ** Interfaces to extend FTS5. Using the interfaces defined in this file, jpayne@69: ** FTS5 may be extended with: jpayne@69: ** jpayne@69: ** * custom tokenizers, and jpayne@69: ** * custom auxiliary functions. jpayne@69: */ jpayne@69: jpayne@69: jpayne@69: #ifndef _FTS5_H jpayne@69: #define _FTS5_H jpayne@69: jpayne@69: jpayne@69: #ifdef __cplusplus jpayne@69: extern "C" { jpayne@69: #endif jpayne@69: jpayne@69: /************************************************************************* jpayne@69: ** CUSTOM AUXILIARY FUNCTIONS jpayne@69: ** jpayne@69: ** Virtual table implementations may overload SQL functions by implementing jpayne@69: ** the sqlite3_module.xFindFunction() method. jpayne@69: */ jpayne@69: jpayne@69: typedef struct Fts5ExtensionApi Fts5ExtensionApi; jpayne@69: typedef struct Fts5Context Fts5Context; jpayne@69: typedef struct Fts5PhraseIter Fts5PhraseIter; jpayne@69: jpayne@69: typedef void (*fts5_extension_function)( jpayne@69: const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ jpayne@69: Fts5Context *pFts, /* First arg to pass to pApi functions */ jpayne@69: sqlite3_context *pCtx, /* Context for returning result/error */ jpayne@69: int nVal, /* Number of values in apVal[] array */ jpayne@69: sqlite3_value **apVal /* Array of trailing arguments */ jpayne@69: ); jpayne@69: jpayne@69: struct Fts5PhraseIter { jpayne@69: const unsigned char *a; jpayne@69: const unsigned char *b; jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** EXTENSION API FUNCTIONS jpayne@69: ** jpayne@69: ** xUserData(pFts): jpayne@69: ** Return a copy of the pUserData pointer passed to the xCreateFunction() jpayne@69: ** API when the extension function was registered. jpayne@69: ** jpayne@69: ** xColumnTotalSize(pFts, iCol, pnToken): jpayne@69: ** If parameter iCol is less than zero, set output variable *pnToken jpayne@69: ** to the total number of tokens in the FTS5 table. Or, if iCol is jpayne@69: ** non-negative but less than the number of columns in the table, return jpayne@69: ** the total number of tokens in column iCol, considering all rows in jpayne@69: ** the FTS5 table. jpayne@69: ** jpayne@69: ** If parameter iCol is greater than or equal to the number of columns jpayne@69: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. jpayne@69: ** an OOM condition or IO error), an appropriate SQLite error code is jpayne@69: ** returned. jpayne@69: ** jpayne@69: ** xColumnCount(pFts): jpayne@69: ** Return the number of columns in the table. jpayne@69: ** jpayne@69: ** xColumnSize(pFts, iCol, pnToken): jpayne@69: ** If parameter iCol is less than zero, set output variable *pnToken jpayne@69: ** to the total number of tokens in the current row. Or, if iCol is jpayne@69: ** non-negative but less than the number of columns in the table, set jpayne@69: ** *pnToken to the number of tokens in column iCol of the current row. jpayne@69: ** jpayne@69: ** If parameter iCol is greater than or equal to the number of columns jpayne@69: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. jpayne@69: ** an OOM condition or IO error), an appropriate SQLite error code is jpayne@69: ** returned. jpayne@69: ** jpayne@69: ** This function may be quite inefficient if used with an FTS5 table jpayne@69: ** created with the "columnsize=0" option. jpayne@69: ** jpayne@69: ** xColumnText: jpayne@69: ** If parameter iCol is less than zero, or greater than or equal to the jpayne@69: ** number of columns in the table, SQLITE_RANGE is returned. jpayne@69: ** jpayne@69: ** Otherwise, this function attempts to retrieve the text of column iCol of jpayne@69: ** the current document. If successful, (*pz) is set to point to a buffer jpayne@69: ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes jpayne@69: ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, jpayne@69: ** if an error occurs, an SQLite error code is returned and the final values jpayne@69: ** of (*pz) and (*pn) are undefined. jpayne@69: ** jpayne@69: ** xPhraseCount: jpayne@69: ** Returns the number of phrases in the current query expression. jpayne@69: ** jpayne@69: ** xPhraseSize: jpayne@69: ** If parameter iCol is less than zero, or greater than or equal to the jpayne@69: ** number of phrases in the current query, as returned by xPhraseCount, jpayne@69: ** 0 is returned. Otherwise, this function returns the number of tokens in jpayne@69: ** phrase iPhrase of the query. Phrases are numbered starting from zero. jpayne@69: ** jpayne@69: ** xInstCount: jpayne@69: ** Set *pnInst to the total number of occurrences of all phrases within jpayne@69: ** the query within the current row. Return SQLITE_OK if successful, or jpayne@69: ** an error code (i.e. SQLITE_NOMEM) if an error occurs. jpayne@69: ** jpayne@69: ** This API can be quite slow if used with an FTS5 table created with the jpayne@69: ** "detail=none" or "detail=column" option. If the FTS5 table is created jpayne@69: ** with either "detail=none" or "detail=column" and "content=" option jpayne@69: ** (i.e. if it is a contentless table), then this API always returns 0. jpayne@69: ** jpayne@69: ** xInst: jpayne@69: ** Query for the details of phrase match iIdx within the current row. jpayne@69: ** Phrase matches are numbered starting from zero, so the iIdx argument jpayne@69: ** should be greater than or equal to zero and smaller than the value jpayne@69: ** output by xInstCount(). If iIdx is less than zero or greater than jpayne@69: ** or equal to the value returned by xInstCount(), SQLITE_RANGE is returned. jpayne@69: ** jpayne@69: ** Otherwise, output parameter *piPhrase is set to the phrase number, *piCol jpayne@69: ** to the column in which it occurs and *piOff the token offset of the jpayne@69: ** first token of the phrase. SQLITE_OK is returned if successful, or an jpayne@69: ** error code (i.e. SQLITE_NOMEM) if an error occurs. jpayne@69: ** jpayne@69: ** This API can be quite slow if used with an FTS5 table created with the jpayne@69: ** "detail=none" or "detail=column" option. jpayne@69: ** jpayne@69: ** xRowid: jpayne@69: ** Returns the rowid of the current row. jpayne@69: ** jpayne@69: ** xTokenize: jpayne@69: ** Tokenize text using the tokenizer belonging to the FTS5 table. jpayne@69: ** jpayne@69: ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): jpayne@69: ** This API function is used to query the FTS table for phrase iPhrase jpayne@69: ** of the current query. Specifically, a query equivalent to: jpayne@69: ** jpayne@69: ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid jpayne@69: ** jpayne@69: ** with $p set to a phrase equivalent to the phrase iPhrase of the jpayne@69: ** current query is executed. Any column filter that applies to jpayne@69: ** phrase iPhrase of the current query is included in $p. For each jpayne@69: ** row visited, the callback function passed as the fourth argument jpayne@69: ** is invoked. The context and API objects passed to the callback jpayne@69: ** function may be used to access the properties of each matched row. jpayne@69: ** Invoking Api.xUserData() returns a copy of the pointer passed as jpayne@69: ** the third argument to pUserData. jpayne@69: ** jpayne@69: ** If parameter iPhrase is less than zero, or greater than or equal to jpayne@69: ** the number of phrases in the query, as returned by xPhraseCount(), jpayne@69: ** this function returns SQLITE_RANGE. jpayne@69: ** jpayne@69: ** If the callback function returns any value other than SQLITE_OK, the jpayne@69: ** query is abandoned and the xQueryPhrase function returns immediately. jpayne@69: ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. jpayne@69: ** Otherwise, the error code is propagated upwards. jpayne@69: ** jpayne@69: ** If the query runs to completion without incident, SQLITE_OK is returned. jpayne@69: ** Or, if some error occurs before the query completes or is aborted by jpayne@69: ** the callback, an SQLite error code is returned. jpayne@69: ** jpayne@69: ** jpayne@69: ** xSetAuxdata(pFts5, pAux, xDelete) jpayne@69: ** jpayne@69: ** Save the pointer passed as the second argument as the extension function's jpayne@69: ** "auxiliary data". The pointer may then be retrieved by the current or any jpayne@69: ** future invocation of the same fts5 extension function made as part of jpayne@69: ** the same MATCH query using the xGetAuxdata() API. jpayne@69: ** jpayne@69: ** Each extension function is allocated a single auxiliary data slot for jpayne@69: ** each FTS query (MATCH expression). If the extension function is invoked jpayne@69: ** more than once for a single FTS query, then all invocations share a jpayne@69: ** single auxiliary data context. jpayne@69: ** jpayne@69: ** If there is already an auxiliary data pointer when this function is jpayne@69: ** invoked, then it is replaced by the new pointer. If an xDelete callback jpayne@69: ** was specified along with the original pointer, it is invoked at this jpayne@69: ** point. jpayne@69: ** jpayne@69: ** The xDelete callback, if one is specified, is also invoked on the jpayne@69: ** auxiliary data pointer after the FTS5 query has finished. jpayne@69: ** jpayne@69: ** If an error (e.g. an OOM condition) occurs within this function, jpayne@69: ** the auxiliary data is set to NULL and an error code returned. If the jpayne@69: ** xDelete parameter was not NULL, it is invoked on the auxiliary data jpayne@69: ** pointer before returning. jpayne@69: ** jpayne@69: ** jpayne@69: ** xGetAuxdata(pFts5, bClear) jpayne@69: ** jpayne@69: ** Returns the current auxiliary data pointer for the fts5 extension jpayne@69: ** function. See the xSetAuxdata() method for details. jpayne@69: ** jpayne@69: ** If the bClear argument is non-zero, then the auxiliary data is cleared jpayne@69: ** (set to NULL) before this function returns. In this case the xDelete, jpayne@69: ** if any, is not invoked. jpayne@69: ** jpayne@69: ** jpayne@69: ** xRowCount(pFts5, pnRow) jpayne@69: ** jpayne@69: ** This function is used to retrieve the total number of rows in the table. jpayne@69: ** In other words, the same value that would be returned by: jpayne@69: ** jpayne@69: ** SELECT count(*) FROM ftstable; jpayne@69: ** jpayne@69: ** xPhraseFirst() jpayne@69: ** This function is used, along with type Fts5PhraseIter and the xPhraseNext jpayne@69: ** method, to iterate through all instances of a single query phrase within jpayne@69: ** the current row. This is the same information as is accessible via the jpayne@69: ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient jpayne@69: ** to use, this API may be faster under some circumstances. To iterate jpayne@69: ** through instances of phrase iPhrase, use the following code: jpayne@69: ** jpayne@69: ** Fts5PhraseIter iter; jpayne@69: ** int iCol, iOff; jpayne@69: ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); jpayne@69: ** iCol>=0; jpayne@69: ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) jpayne@69: ** ){ jpayne@69: ** // An instance of phrase iPhrase at offset iOff of column iCol jpayne@69: ** } jpayne@69: ** jpayne@69: ** The Fts5PhraseIter structure is defined above. Applications should not jpayne@69: ** modify this structure directly - it should only be used as shown above jpayne@69: ** with the xPhraseFirst() and xPhraseNext() API methods (and by jpayne@69: ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). jpayne@69: ** jpayne@69: ** This API can be quite slow if used with an FTS5 table created with the jpayne@69: ** "detail=none" or "detail=column" option. If the FTS5 table is created jpayne@69: ** with either "detail=none" or "detail=column" and "content=" option jpayne@69: ** (i.e. if it is a contentless table), then this API always iterates jpayne@69: ** through an empty set (all calls to xPhraseFirst() set iCol to -1). jpayne@69: ** jpayne@69: ** xPhraseNext() jpayne@69: ** See xPhraseFirst above. jpayne@69: ** jpayne@69: ** xPhraseFirstColumn() jpayne@69: ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() jpayne@69: ** and xPhraseNext() APIs described above. The difference is that instead jpayne@69: ** of iterating through all instances of a phrase in the current row, these jpayne@69: ** APIs are used to iterate through the set of columns in the current row jpayne@69: ** that contain one or more instances of a specified phrase. For example: jpayne@69: ** jpayne@69: ** Fts5PhraseIter iter; jpayne@69: ** int iCol; jpayne@69: ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); jpayne@69: ** iCol>=0; jpayne@69: ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) jpayne@69: ** ){ jpayne@69: ** // Column iCol contains at least one instance of phrase iPhrase jpayne@69: ** } jpayne@69: ** jpayne@69: ** This API can be quite slow if used with an FTS5 table created with the jpayne@69: ** "detail=none" option. If the FTS5 table is created with either jpayne@69: ** "detail=none" "content=" option (i.e. if it is a contentless table), jpayne@69: ** then this API always iterates through an empty set (all calls to jpayne@69: ** xPhraseFirstColumn() set iCol to -1). jpayne@69: ** jpayne@69: ** The information accessed using this API and its companion jpayne@69: ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext jpayne@69: ** (or xInst/xInstCount). The chief advantage of this API is that it is jpayne@69: ** significantly more efficient than those alternatives when used with jpayne@69: ** "detail=column" tables. jpayne@69: ** jpayne@69: ** xPhraseNextColumn() jpayne@69: ** See xPhraseFirstColumn above. jpayne@69: ** jpayne@69: ** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken) jpayne@69: ** This is used to access token iToken of phrase iPhrase of the current jpayne@69: ** query. Before returning, output parameter *ppToken is set to point jpayne@69: ** to a buffer containing the requested token, and *pnToken to the jpayne@69: ** size of this buffer in bytes. jpayne@69: ** jpayne@69: ** If iPhrase or iToken are less than zero, or if iPhrase is greater than jpayne@69: ** or equal to the number of phrases in the query as reported by jpayne@69: ** xPhraseCount(), or if iToken is equal to or greater than the number of jpayne@69: ** tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken jpayne@69: are both zeroed. jpayne@69: ** jpayne@69: ** The output text is not a copy of the query text that specified the jpayne@69: ** token. It is the output of the tokenizer module. For tokendata=1 jpayne@69: ** tables, this includes any embedded 0x00 and trailing data. jpayne@69: ** jpayne@69: ** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken) jpayne@69: ** This is used to access token iToken of phrase hit iIdx within the jpayne@69: ** current row. If iIdx is less than zero or greater than or equal to the jpayne@69: ** value returned by xInstCount(), SQLITE_RANGE is returned. Otherwise, jpayne@69: ** output variable (*ppToken) is set to point to a buffer containing the jpayne@69: ** matching document token, and (*pnToken) to the size of that buffer in jpayne@69: ** bytes. This API is not available if the specified token matches a jpayne@69: ** prefix query term. In that case both output variables are always set jpayne@69: ** to 0. jpayne@69: ** jpayne@69: ** The output text is not a copy of the document text that was tokenized. jpayne@69: ** It is the output of the tokenizer module. For tokendata=1 tables, this jpayne@69: ** includes any embedded 0x00 and trailing data. jpayne@69: ** jpayne@69: ** This API can be quite slow if used with an FTS5 table created with the jpayne@69: ** "detail=none" or "detail=column" option. jpayne@69: */ jpayne@69: struct Fts5ExtensionApi { jpayne@69: int iVersion; /* Currently always set to 3 */ jpayne@69: jpayne@69: void *(*xUserData)(Fts5Context*); jpayne@69: jpayne@69: int (*xColumnCount)(Fts5Context*); jpayne@69: int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); jpayne@69: int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); jpayne@69: jpayne@69: int (*xTokenize)(Fts5Context*, jpayne@69: const char *pText, int nText, /* Text to tokenize */ jpayne@69: void *pCtx, /* Context passed to xToken() */ jpayne@69: int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ jpayne@69: ); jpayne@69: jpayne@69: int (*xPhraseCount)(Fts5Context*); jpayne@69: int (*xPhraseSize)(Fts5Context*, int iPhrase); jpayne@69: jpayne@69: int (*xInstCount)(Fts5Context*, int *pnInst); jpayne@69: int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); jpayne@69: jpayne@69: sqlite3_int64 (*xRowid)(Fts5Context*); jpayne@69: int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); jpayne@69: int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); jpayne@69: jpayne@69: int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, jpayne@69: int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) jpayne@69: ); jpayne@69: int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); jpayne@69: void *(*xGetAuxdata)(Fts5Context*, int bClear); jpayne@69: jpayne@69: int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); jpayne@69: void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); jpayne@69: jpayne@69: int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); jpayne@69: void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); jpayne@69: jpayne@69: /* Below this point are iVersion>=3 only */ jpayne@69: int (*xQueryToken)(Fts5Context*, jpayne@69: int iPhrase, int iToken, jpayne@69: const char **ppToken, int *pnToken jpayne@69: ); jpayne@69: int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*); jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** CUSTOM AUXILIARY FUNCTIONS jpayne@69: *************************************************************************/ jpayne@69: jpayne@69: /************************************************************************* jpayne@69: ** CUSTOM TOKENIZERS jpayne@69: ** jpayne@69: ** Applications may also register custom tokenizer types. A tokenizer jpayne@69: ** is registered by providing fts5 with a populated instance of the jpayne@69: ** following structure. All structure methods must be defined, setting jpayne@69: ** any member of the fts5_tokenizer struct to NULL leads to undefined jpayne@69: ** behaviour. The structure methods are expected to function as follows: jpayne@69: ** jpayne@69: ** xCreate: jpayne@69: ** This function is used to allocate and initialize a tokenizer instance. jpayne@69: ** A tokenizer instance is required to actually tokenize text. jpayne@69: ** jpayne@69: ** The first argument passed to this function is a copy of the (void*) jpayne@69: ** pointer provided by the application when the fts5_tokenizer object jpayne@69: ** was registered with FTS5 (the third argument to xCreateTokenizer()). jpayne@69: ** The second and third arguments are an array of nul-terminated strings jpayne@69: ** containing the tokenizer arguments, if any, specified following the jpayne@69: ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used jpayne@69: ** to create the FTS5 table. jpayne@69: ** jpayne@69: ** The final argument is an output variable. If successful, (*ppOut) jpayne@69: ** should be set to point to the new tokenizer handle and SQLITE_OK jpayne@69: ** returned. If an error occurs, some value other than SQLITE_OK should jpayne@69: ** be returned. In this case, fts5 assumes that the final value of *ppOut jpayne@69: ** is undefined. jpayne@69: ** jpayne@69: ** xDelete: jpayne@69: ** This function is invoked to delete a tokenizer handle previously jpayne@69: ** allocated using xCreate(). Fts5 guarantees that this function will jpayne@69: ** be invoked exactly once for each successful call to xCreate(). jpayne@69: ** jpayne@69: ** xTokenize: jpayne@69: ** This function is expected to tokenize the nText byte string indicated jpayne@69: ** by argument pText. pText may or may not be nul-terminated. The first jpayne@69: ** argument passed to this function is a pointer to an Fts5Tokenizer object jpayne@69: ** returned by an earlier call to xCreate(). jpayne@69: ** jpayne@69: ** The second argument indicates the reason that FTS5 is requesting jpayne@69: ** tokenization of the supplied text. This is always one of the following jpayne@69: ** four values: jpayne@69: ** jpayne@69: **
  • FTS5_TOKENIZE_DOCUMENT - A document is being inserted into jpayne@69: ** or removed from the FTS table. The tokenizer is being invoked to jpayne@69: ** determine the set of tokens to add to (or delete from) the jpayne@69: ** FTS index. jpayne@69: ** jpayne@69: **
  • FTS5_TOKENIZE_QUERY - A MATCH query is being executed jpayne@69: ** against the FTS index. The tokenizer is being called to tokenize jpayne@69: ** a bareword or quoted string specified as part of the query. jpayne@69: ** jpayne@69: **
  • (FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX) - Same as jpayne@69: ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is jpayne@69: ** followed by a "*" character, indicating that the last token jpayne@69: ** returned by the tokenizer will be treated as a token prefix. jpayne@69: ** jpayne@69: **
  • FTS5_TOKENIZE_AUX - The tokenizer is being invoked to jpayne@69: ** satisfy an fts5_api.xTokenize() request made by an auxiliary jpayne@69: ** function. Or an fts5_api.xColumnSize() request made by the same jpayne@69: ** on a columnsize=0 database. jpayne@69: **
jpayne@69: ** jpayne@69: ** For each token in the input string, the supplied callback xToken() must jpayne@69: ** be invoked. The first argument to it should be a copy of the pointer jpayne@69: ** passed as the second argument to xTokenize(). The third and fourth jpayne@69: ** arguments are a pointer to a buffer containing the token text, and the jpayne@69: ** size of the token in bytes. The 4th and 5th arguments are the byte offsets jpayne@69: ** of the first byte of and first byte immediately following the text from jpayne@69: ** which the token is derived within the input. jpayne@69: ** jpayne@69: ** The second argument passed to the xToken() callback ("tflags") should jpayne@69: ** normally be set to 0. The exception is if the tokenizer supports jpayne@69: ** synonyms. In this case see the discussion below for details. jpayne@69: ** jpayne@69: ** FTS5 assumes the xToken() callback is invoked for each token in the jpayne@69: ** order that they occur within the input text. jpayne@69: ** jpayne@69: ** If an xToken() callback returns any value other than SQLITE_OK, then jpayne@69: ** the tokenization should be abandoned and the xTokenize() method should jpayne@69: ** immediately return a copy of the xToken() return value. Or, if the jpayne@69: ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, jpayne@69: ** if an error occurs with the xTokenize() implementation itself, it jpayne@69: ** may abandon the tokenization and return any error code other than jpayne@69: ** SQLITE_OK or SQLITE_DONE. jpayne@69: ** jpayne@69: ** SYNONYM SUPPORT jpayne@69: ** jpayne@69: ** Custom tokenizers may also support synonyms. Consider a case in which a jpayne@69: ** user wishes to query for a phrase such as "first place". Using the jpayne@69: ** built-in tokenizers, the FTS5 query 'first + place' will match instances jpayne@69: ** of "first place" within the document set, but not alternative forms jpayne@69: ** such as "1st place". In some applications, it would be better to match jpayne@69: ** all instances of "first place" or "1st place" regardless of which form jpayne@69: ** the user specified in the MATCH query text. jpayne@69: ** jpayne@69: ** There are several ways to approach this in FTS5: jpayne@69: ** jpayne@69: **
  1. By mapping all synonyms to a single token. In this case, using jpayne@69: ** the above example, this means that the tokenizer returns the jpayne@69: ** same token for inputs "first" and "1st". Say that token is in jpayne@69: ** fact "first", so that when the user inserts the document "I won jpayne@69: ** 1st place" entries are added to the index for tokens "i", "won", jpayne@69: ** "first" and "place". If the user then queries for '1st + place', jpayne@69: ** the tokenizer substitutes "first" for "1st" and the query works jpayne@69: ** as expected. jpayne@69: ** jpayne@69: **
  2. By querying the index for all synonyms of each query term jpayne@69: ** separately. In this case, when tokenizing query text, the jpayne@69: ** tokenizer may provide multiple synonyms for a single term jpayne@69: ** within the document. FTS5 then queries the index for each jpayne@69: ** synonym individually. For example, faced with the query: jpayne@69: ** jpayne@69: ** jpayne@69: ** ... MATCH 'first place' jpayne@69: ** jpayne@69: ** the tokenizer offers both "1st" and "first" as synonyms for the jpayne@69: ** first token in the MATCH query and FTS5 effectively runs a query jpayne@69: ** similar to: jpayne@69: ** jpayne@69: ** jpayne@69: ** ... MATCH '(first OR 1st) place' jpayne@69: ** jpayne@69: ** except that, for the purposes of auxiliary functions, the query jpayne@69: ** still appears to contain just two phrases - "(first OR 1st)" jpayne@69: ** being treated as a single phrase. jpayne@69: ** jpayne@69: **
  3. By adding multiple synonyms for a single term to the FTS index. jpayne@69: ** Using this method, when tokenizing document text, the tokenizer jpayne@69: ** provides multiple synonyms for each token. So that when a jpayne@69: ** document such as "I won first place" is tokenized, entries are jpayne@69: ** added to the FTS index for "i", "won", "first", "1st" and jpayne@69: ** "place". jpayne@69: ** jpayne@69: ** This way, even if the tokenizer does not provide synonyms jpayne@69: ** when tokenizing query text (it should not - to do so would be jpayne@69: ** inefficient), it doesn't matter if the user queries for jpayne@69: ** 'first + place' or '1st + place', as there are entries in the jpayne@69: ** FTS index corresponding to both forms of the first token. jpayne@69: **
jpayne@69: ** jpayne@69: ** Whether it is parsing document or query text, any call to xToken that jpayne@69: ** specifies a tflags argument with the FTS5_TOKEN_COLOCATED bit jpayne@69: ** is considered to supply a synonym for the previous token. For example, jpayne@69: ** when parsing the document "I won first place", a tokenizer that supports jpayne@69: ** synonyms would call xToken() 5 times, as follows: jpayne@69: ** jpayne@69: ** jpayne@69: ** xToken(pCtx, 0, "i", 1, 0, 1); jpayne@69: ** xToken(pCtx, 0, "won", 3, 2, 5); jpayne@69: ** xToken(pCtx, 0, "first", 5, 6, 11); jpayne@69: ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); jpayne@69: ** xToken(pCtx, 0, "place", 5, 12, 17); jpayne@69: ** jpayne@69: ** jpayne@69: ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time jpayne@69: ** xToken() is called. Multiple synonyms may be specified for a single token jpayne@69: ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. jpayne@69: ** There is no limit to the number of synonyms that may be provided for a jpayne@69: ** single token. jpayne@69: ** jpayne@69: ** In many cases, method (1) above is the best approach. It does not add jpayne@69: ** extra data to the FTS index or require FTS5 to query for multiple terms, jpayne@69: ** so it is efficient in terms of disk space and query speed. However, it jpayne@69: ** does not support prefix queries very well. If, as suggested above, the jpayne@69: ** token "first" is substituted for "1st" by the tokenizer, then the query: jpayne@69: ** jpayne@69: ** jpayne@69: ** ... MATCH '1s*' jpayne@69: ** jpayne@69: ** will not match documents that contain the token "1st" (as the tokenizer jpayne@69: ** will probably not map "1s" to any prefix of "first"). jpayne@69: ** jpayne@69: ** For full prefix support, method (3) may be preferred. In this case, jpayne@69: ** because the index contains entries for both "first" and "1st", prefix jpayne@69: ** queries such as 'fi*' or '1s*' will match correctly. However, because jpayne@69: ** extra entries are added to the FTS index, this method uses more space jpayne@69: ** within the database. jpayne@69: ** jpayne@69: ** Method (2) offers a midpoint between (1) and (3). Using this method, jpayne@69: ** a query such as '1s*' will match documents that contain the literal jpayne@69: ** token "1st", but not "first" (assuming the tokenizer is not able to jpayne@69: ** provide synonyms for prefixes). However, a non-prefix query like '1st' jpayne@69: ** will match against "1st" and "first". This method does not require jpayne@69: ** extra disk space, as no extra entries are added to the FTS index. jpayne@69: ** On the other hand, it may require more CPU cycles to run MATCH queries, jpayne@69: ** as separate queries of the FTS index are required for each synonym. jpayne@69: ** jpayne@69: ** When using methods (2) or (3), it is important that the tokenizer only jpayne@69: ** provide synonyms when tokenizing document text (method (3)) or query jpayne@69: ** text (method (2)), not both. Doing so will not cause any errors, but is jpayne@69: ** inefficient. jpayne@69: */ jpayne@69: typedef struct Fts5Tokenizer Fts5Tokenizer; jpayne@69: typedef struct fts5_tokenizer fts5_tokenizer; jpayne@69: struct fts5_tokenizer { jpayne@69: int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); jpayne@69: void (*xDelete)(Fts5Tokenizer*); jpayne@69: int (*xTokenize)(Fts5Tokenizer*, jpayne@69: void *pCtx, jpayne@69: int flags, /* Mask of FTS5_TOKENIZE_* flags */ jpayne@69: const char *pText, int nText, jpayne@69: int (*xToken)( jpayne@69: void *pCtx, /* Copy of 2nd argument to xTokenize() */ jpayne@69: int tflags, /* Mask of FTS5_TOKEN_* flags */ jpayne@69: const char *pToken, /* Pointer to buffer containing token */ jpayne@69: int nToken, /* Size of token in bytes */ jpayne@69: int iStart, /* Byte offset of token within input text */ jpayne@69: int iEnd /* Byte offset of end of token within input text */ jpayne@69: ) jpayne@69: ); jpayne@69: }; jpayne@69: jpayne@69: /* Flags that may be passed as the third argument to xTokenize() */ jpayne@69: #define FTS5_TOKENIZE_QUERY 0x0001 jpayne@69: #define FTS5_TOKENIZE_PREFIX 0x0002 jpayne@69: #define FTS5_TOKENIZE_DOCUMENT 0x0004 jpayne@69: #define FTS5_TOKENIZE_AUX 0x0008 jpayne@69: jpayne@69: /* Flags that may be passed by the tokenizer implementation back to FTS5 jpayne@69: ** as the third argument to the supplied xToken callback. */ jpayne@69: #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ jpayne@69: jpayne@69: /* jpayne@69: ** END OF CUSTOM TOKENIZERS jpayne@69: *************************************************************************/ jpayne@69: jpayne@69: /************************************************************************* jpayne@69: ** FTS5 EXTENSION REGISTRATION API jpayne@69: */ jpayne@69: typedef struct fts5_api fts5_api; jpayne@69: struct fts5_api { jpayne@69: int iVersion; /* Currently always set to 2 */ jpayne@69: jpayne@69: /* Create a new tokenizer */ jpayne@69: int (*xCreateTokenizer)( jpayne@69: fts5_api *pApi, jpayne@69: const char *zName, jpayne@69: void *pUserData, jpayne@69: fts5_tokenizer *pTokenizer, jpayne@69: void (*xDestroy)(void*) jpayne@69: ); jpayne@69: jpayne@69: /* Find an existing tokenizer */ jpayne@69: int (*xFindTokenizer)( jpayne@69: fts5_api *pApi, jpayne@69: const char *zName, jpayne@69: void **ppUserData, jpayne@69: fts5_tokenizer *pTokenizer jpayne@69: ); jpayne@69: jpayne@69: /* Create a new auxiliary function */ jpayne@69: int (*xCreateFunction)( jpayne@69: fts5_api *pApi, jpayne@69: const char *zName, jpayne@69: void *pUserData, jpayne@69: fts5_extension_function xFunction, jpayne@69: void (*xDestroy)(void*) jpayne@69: ); jpayne@69: }; jpayne@69: jpayne@69: /* jpayne@69: ** END OF REGISTRATION API jpayne@69: *************************************************************************/ jpayne@69: jpayne@69: #ifdef __cplusplus jpayne@69: } /* end of the 'extern "C"' block */ jpayne@69: #endif jpayne@69: jpayne@69: #endif /* _FTS5_H */ jpayne@69: jpayne@69: /******** End of fts5.h *********/