NAME
DBIx::Class::SQLMaker::OracleJoins - Pre-ANSI Joins-via-Where-Clause Syntax
PURPOSE
This module was originally written to support Oracle < 9i where ANSI joins weren't supported at all, but became the module for Oracle >= 8 because Oracle's optimising of ANSI joins is horrible.
SYNOPSIS
Not intended for use directly; used as the sql_maker_class for schemas and components.
DESCRIPTION
Implements pre-ANSI joins specified in the where clause. Instead of:
SELECT x FROM y JOIN z ON y.id = z.id
It will write:
SELECT x FROM y, z WHERE y.id = z.id
It should properly support left joins, and right joins. Full outer joins are not possible due to the fact that Oracle requires the entire query be written to union the results of a left and right join, and by the time this module is called to create the where query and table definition part of the sql query, it's already too late.
METHODS
- select ($\@$;$$@)
-
Replaces DBIx::Class::SQLMaker's select() method, which calls _oracle_joins() to modify the column and table list before calling SUPER::select().
- _recurse_from ($$\@)
-
Recursive subroutine that builds the table list.
- _oracle_joins ($$$@)
-
Creates the left/right relationship in the where query.
BUGS
Does not support full outer joins. Probably lots more.
SEE ALSO
- DBIx::Class::Storage::DBI::Oracle::WhereJoins - Storage class using this
- DBIx::Class::SQLMaker - Parent module
- DBIx::Class - Duh
AUTHOR
Justin Wheeler <jwheeler@datademons.com>
CONTRIBUTORS
David Jack Olrik <djo@cpan.org>
LICENSE
This module is licensed under the same terms as Perl itself.