jpayne@68: # tdbcpostgres.tcl --
jpayne@68: #
jpayne@68: #	Class definitions and Tcl-level methods for the tdbc::postgres bridge.
jpayne@68: #
jpayne@68: # Copyright (c) 2009 by Slawomir Cygan
jpayne@68: #
jpayne@68: # See the file "license.terms" for information on usage and redistribution
jpayne@68: # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
jpayne@68: #
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: 
jpayne@68: package require tdbc
jpayne@68: 
jpayne@68: ::namespace eval ::tdbc::mypostgres {
jpayne@68: 
jpayne@68:     namespace export connection datasources drivers
jpayne@68: 
jpayne@68: }
jpayne@68: 
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: #
jpayne@68: # tdbc::postgres::connection --
jpayne@68: #
jpayne@68: #	Class representing a connection to a Postgres database.
jpayne@68: #
jpayne@68: #-------------------------------------------------------------------------------
jpayne@68: 
jpayne@68: ::oo::class create ::tdbc::postgres::connection {
jpayne@68: 
jpayne@68:     superclass ::tdbc::connection
jpayne@68: 
jpayne@68:     # The constructor is written in C. It takes alternating keywords
jpayne@68:     # and values pairs as its arguments.  (See the manual page for the
jpayne@68:     # available options.)
jpayne@68: 
jpayne@68:     # The 'statementCreate' method delegates to the constructor of the
jpayne@68:     # statement class
jpayne@68: 
jpayne@68:     forward statementCreate ::tdbc::postgres::statement create
jpayne@68: 
jpayne@68: 
jpayne@68:     # The 'prepareCall' method gives a portable interface to prepare
jpayne@68:     # calls to stored procedures.  It delegates to 'prepare' to do the
jpayne@68:     # actual work.
jpayne@68: 
jpayne@68:     method preparecall {call} {
jpayne@68: 	regexp {^[[:space:]]*(?:([A-Za-z_][A-Za-z_0-9]*)[[:space:]]*=)?(.*)} \
jpayne@68: 	    $call -> varName rest
jpayne@68: 	if {$varName eq {}} {
jpayne@68: 	    my prepare \\{$rest\\}
jpayne@68: 	} else {
jpayne@68: 	    my prepare \\{:$varName=$rest\\}
jpayne@68: 	}
jpayne@68:     }
jpayne@68: 
jpayne@68:     # The 'init', 'begintransaction', 'commit, 'rollback', 'tables'
jpayne@68:     #  and 'columns' methods are implemented in C.
jpayne@68: 
jpayne@68: }
jpayne@68: 
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: #
jpayne@68: # tdbc::postgres::statement --
jpayne@68: #
jpayne@68: #	The class 'tdbc::postgres::statement' models one statement against a
jpayne@68: #       database accessed through a Postgres connection
jpayne@68: #
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: 
jpayne@68: ::oo::class create ::tdbc::postgres::statement {
jpayne@68: 
jpayne@68:     superclass ::tdbc::statement
jpayne@68: 
jpayne@68:     # The 'resultSetCreate' method forwards to the constructor of the
jpayne@68:     # result set.
jpayne@68: 
jpayne@68:     forward resultSetCreate ::tdbc::postgres::resultset create
jpayne@68: 
jpayne@68:     # Methods implemented in C:
jpayne@68:     #
jpayne@68:     # constructor connection SQLCode
jpayne@68:     #	The constructor accepts the handle to the connection and the SQL code
jpayne@68:     #	for the statement to prepare.  It creates a subordinate namespace to
jpayne@68:     #	hold the statement's active result sets, and then delegates to the
jpayne@68:     #	'init' method, written in C, to do the actual work of preparing the
jpayne@68:     #	statement.
jpayne@68:     # params
jpayne@68:     #   Returns descriptions of the parameters of a statement.
jpayne@68:     # paramtype paramname ?direction? type ?precision ?scale??
jpayne@68:     #   Declares the type of a parameter in the statement
jpayne@68: 
jpayne@68: }
jpayne@68: 
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: #
jpayne@68: # tdbc::postgres::resultset --
jpayne@68: #
jpayne@68: #	The class 'tdbc::postgres::resultset' models the result set that is
jpayne@68: #	produced by executing a statement against a Postgres database.
jpayne@68: #
jpayne@68: #------------------------------------------------------------------------------
jpayne@68: 
jpayne@68: ::oo::class create ::tdbc::postgres::resultset {
jpayne@68: 
jpayne@68:     superclass ::tdbc::resultset
jpayne@68: 
jpayne@68:     # The 'nextresults' method is stubbed out; tdbcpostgres does not
jpayne@68:     # allow a single call to return multiple results.
jpayne@68: 
jpayne@68:     method nextresults {} {
jpayne@68: 	while {[my nextdict rubbish]} {}
jpayne@68: 	return 0
jpayne@68:     }
jpayne@68: 
jpayne@68:     # Methods implemented in C include:
jpayne@68: 
jpayne@68:     # constructor statement ?dictionary?
jpayne@68:     #     -- Executes the statement against the database, optionally providing
jpayne@68:     #        a dictionary of substituted parameters (default is to get params
jpayne@68:     #        from variables in the caller's scope).
jpayne@68:     # columns
jpayne@68:     #     -- Returns a list of the names of the columns in the result.
jpayne@68:     # nextdict
jpayne@68:     #     -- Stores the next row of the result set in the given variable in
jpayne@68:     #        the caller's scope as a dictionary whose keys are
jpayne@68:     #        column names and whose values are column values, or else
jpayne@68:     #        as a list of cells.
jpayne@68:     # nextlist
jpayne@68:     #     -- Stores the next row of the result set in the given variable in
jpayne@68:     #        the caller's scope as a list of cells.
jpayne@68:     # rowcount
jpayne@68:     #     -- Returns a count of rows affected by the statement, or -1
jpayne@68:     #        if the count of rows has not been determined.
jpayne@68: 
jpayne@68: }