[Rt-commit] r2563 - in DBIx-SearchBuilder/trunk: . SearchBuilder

[jesse at bestpractical.com]

Author: jesse
Date: Sun Apr  3 05:11:14 2005
New Revision: 2563

Added:
   DBIx-SearchBuilder/trunk/SearchBuilder/Unique.pm
Modified:
   DBIx-SearchBuilder/trunk/   (props changed)
   DBIx-SearchBuilder/trunk/Changes
   DBIx-SearchBuilder/trunk/MANIFEST
Log:
 r11660 at hualien:  jesse | 2005-04-03 17:09:15 +0800
 * Added a SearchBuilder::Unique subclass


Modified: DBIx-SearchBuilder/trunk/Changes
==============================================================================
--- DBIx-SearchBuilder/trunk/Changes	(original)
+++ DBIx-SearchBuilder/trunk/Changes	Sun Apr  3 05:11:14 2005
@@ -1,5 +1,7 @@
 Revision history for Perl extension DBIx::SearchBuilder.
 
+    - Added a new "SearchBuilder::Unique module for uniquifying search results
+
 
 1.23
     - Now use DBI->quote_identifier to quote column and table names (Ruslan)

Modified: DBIx-SearchBuilder/trunk/MANIFEST
==============================================================================
--- DBIx-SearchBuilder/trunk/MANIFEST	(original)
+++ DBIx-SearchBuilder/trunk/MANIFEST	Sun Apr  3 05:11:14 2005
@@ -19,6 +19,7 @@
 SearchBuilder/Record.pm
 SearchBuilder/Record/Cachable.pm
 SearchBuilder/Union.pm
+SearchBuilder/Unique.pm
 t/00.load.t
 t/01records.t
 t/02records_object.t

Added: DBIx-SearchBuilder/trunk/SearchBuilder/Unique.pm
==============================================================================
--- (empty file)
+++ DBIx-SearchBuilder/trunk/SearchBuilder/Unique.pm	Sun Apr  3 05:11:14 2005
@@ -0,0 +1,66 @@
+package DBIx::SearchBuilder::Unique;
+use base 'Exporter';
+our @EXPORT = qw(AddRecord);
+our $VERSION = "0.01";
+use strict;
+use warnings;
+
+
+
+sub AddRecord {
+    my $self = shift;
+    my $record = shift;
+
+    # We're a mixin, so we can't override _CleanSlate, but if an object
+    # gets reused, we need to clean ourselves out.  If there are no items,
+    # we're clearly doing a new search
+    $self->{"dbix_sb_unique_cache"} = {} unless (@{$self->{'items'}}[0]);
+    return if $self->{"dbix_sb_unique_cache"}->{$record->id}++;
+    push @{$self->{'items'}}, $record;
+    $self->{'rows'}++;
+}
+
+1;
+
+=head1 NAME
+
+DBIx::SearchBuilder::Unique - Ensure uniqueness of records in a collection
+
+=head1 SYNOPSIS
+
+    package Foo::Collection;
+    use base 'DBIx::SearchBuilder';
+
+    use DBIx::SearchBuilder::Unique; # mixin
+
+    my $collection = Foo::Collection->New();
+    $collection->SetupComplicatedJoins;
+    $collection->OrderByMagic;
+    
+    while (my $thing = $collection->Next) {
+        # $thing is going to be distinct
+    }
+
+=head1 DESCRIPTION
+
+Currently, DBIx::SearchBuilder makes exceptions for databases which
+cannot handle both C<SELECT DISTINCT> and ordering in the same
+statement; it drops the C<DISTINCT> requirement. This, of course, means
+that you can get the same row twice, which you might not want. If that's
+the case, use this module as a mix-in, and it will provide you with an
+C<AddRecord> method which ensures that a record will not appear twice in
+the same search.
+
+=head1 AUTHOR
+
+Simon Cozens.
+
+=head1 COPYRIGHT
+
+Copyright 2005 Best Practical Solutions, LLC
+
+This library is free software; you can redistribute it and/or modify it
+under the same terms as Perl itself.
+
+=cut
+