From: Peter Rabbitson <ribasushi@cpan.org>
Date: Thu, 3 Dec 2009 09:03:18 +0000 (+0000)
Subject: The correct top100 mssql solution and test
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=f0bd60fc51329ed3c6cd16de4157477e075d4058;p=dbsrgits%2FDBIx-Class-Historic.git

The correct top100 mssql solution and test
---

diff --git a/lib/DBIx/Class/Storage/DBI/MSSQL.pm b/lib/DBIx/Class/Storage/DBI/MSSQL.pm
index 94597ab..4add28c 100644
--- a/lib/DBIx/Class/Storage/DBI/MSSQL.pm
+++ b/lib/DBIx/Class/Storage/DBI/MSSQL.pm
@@ -178,6 +178,31 @@ sub _execute {
 
 sub last_insert_id { shift->_identity }
 
+#
+# MSSQL is retarded wrt ordered subselects. One needs to add a TOP 100%
+# to *all* subqueries, do it here.
+#
+sub _select_args_to_query {
+  my $self = shift;
+
+  my $sql_maker = $self->sql_maker;
+  my ($op, $bind, $ident, $bind_attrs, $select, $cond, $order) = $self->_select_args(@_);
+
+  if (not scalar $sql_maker->_order_by_chunks ($order->{order_by}) ) {
+    # no ordering, just short circuit
+    return $self->next::method (@_);
+  }
+
+  my ($sql, $bind, @rest) = $self->next::method (@_);
+  $sql =~ s/^ \s* SELECT \s/SELECT TOP 100 PERCENT /xi;
+
+  return wantarray
+    ? ($sql, $bind, @rest)
+    : \[ "($sql)", @$bind ]
+  ;
+}
+
+
 # savepoint syntax is the same as in Sybase ASE
 
 sub _svp_begin {
diff --git a/t/746mssql.t b/t/746mssql.t
index f120c12..f474010 100644
--- a/t/746mssql.t
+++ b/t/746mssql.t
@@ -249,6 +249,20 @@ lives_ok ( sub {
   ]);
 }, 'populate without PKs supplied ok' );
 
+# make sure ordered subselects work
+{
+  my $book_owner_ids = $schema->resultset ('BooksInLibrary')
+                               ->search ({}, { join => 'owner', distinct => 1, order_by => { -desc => 'owner'} })
+                                ->get_column ('owner');
+
+  my $owners = $schema->resultset ('Owners')->search ({
+    id => { -in => $book_owner_ids->as_query }
+  });
+
+  is ($owners->count, 8, 'Correct amount of book owners');
+  is ($owners->all, 8, 'Correct amount of book owner objects');
+}
+
 #
 # try a prefetch on tables with identically named columns
 #