From: Matt S Trout <mst@shadowcat.co.uk>
Date: Fri, 20 Apr 2012 03:20:25 +0000 (+0000)
Subject: Variation of dq's d35a4e048 - sanify multiplying join prune
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=437a9cfaa7ef361284eee806578be7690a229ff8;p=dbsrgits%2FDBIx-Class-Historic.git

Variation of dq's d35a4e048 - sanify multiplying join prune

Use a private more descriptive attr name
---

diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 4792391..2e6c783 100644
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -1885,7 +1885,10 @@ sub _rs_update_delete {
     # make a new $rs selecting only the PKs (that's all we really need for the subq)
     delete $attrs->{$_} for qw/select as collapse _related_results_construction/;
     $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
-    $attrs->{group_by} = \ '';  # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
+
+    # this will be consumed by the pruner waaaaay down the stack
+    $attrs->{_force_prune_multiplying_joins} = 1;
+
     my $subrs = (ref $self)->new($rsrc, $attrs);
 
     if (@$idcols == 1) {
diff --git a/lib/DBIx/Class/Storage/DBIHacks.pm b/lib/DBIx/Class/Storage/DBIHacks.pm
index a9f3bff..fd290f0 100644
--- a/lib/DBIx/Class/Storage/DBIHacks.pm
+++ b/lib/DBIx/Class/Storage/DBIHacks.pm
@@ -24,7 +24,7 @@ use namespace::clean;
 #
 sub _prune_unused_joins {
   my $self = shift;
-  my ($from, $select, $where, $attrs, $ignore_multiplication) = @_;
+  my ($from, $select, $where, $attrs) = @_;
 
   return $from unless $self->_use_join_optimizer;
 
@@ -40,7 +40,7 @@ sub _prune_unused_joins {
   # a grouped set will not be affected by amount of rows. Thus any
   # {multiplying} joins can go
   delete $aliastypes->{multiplying}
-    if $ignore_multiplication or $attrs->{group_by};
+    if $attrs->{_force_prune_multiplying_joins} or $attrs->{group_by};
 
   my @newfrom = $from->[0]; # FROM head is always present
 
@@ -175,7 +175,9 @@ sub _adjust_select_args_for_complex_prefetch {
     local $self->{_use_join_optimizer} = 1;
 
     # throw away multijoins since we def. do not care about those inside the subquery
-    my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, $inner_attrs, 'ignore_multiplication');
+    my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, {
+      %$inner_attrs, _force_prune_multiplying_joins => 1
+    });
 
     my $inner_aliastypes =
       $self->_resolve_aliastypes_from_select_args( $inner_from, $inner_select, $where, $inner_attrs );