X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FOrdered.pm;h=8e2c74dc2786214eff7dd6f8fc3a35ce1b414961;hb=dd3583f282f6807ac7857c2d6b7a3ddd85a11ab4;hp=f721c69617f477d88fb09b6a36e02a8edb643810;hpb=fe82b6cf92f6dfd891c90c7e28bcffd9966b039b;p=dbsrgits%2FDBIx-Class-Historic.git

diff --git a/lib/DBIx/Class/Ordered.pm b/lib/DBIx/Class/Ordered.pm
index f721c69..8e2c74d 100644
--- a/lib/DBIx/Class/Ordered.pm
+++ b/lib/DBIx/Class/Ordered.pm
@@ -279,20 +279,18 @@ sub move_to {
     my $from_position = $self->get_column( $position_column );
     return 0 if ( $to_position < 1 );
     return 0 if ( $from_position==$to_position );
+    my @between = (
+        ( $from_position < $to_position )
+        ? ( $from_position+1, $to_position )
+        : ( $to_position, $from_position-1 )
+    );
     my $rs = $self->result_source->resultset->search({
-        -and => [
-            $position_column =>
-              { -between => [ $from_position, $to_position ] },
-        ],
+        $position_column => { -between => [ @between ] },
         $self->_grouping_clause(),
     });
     my $op = ($from_position>$to_position) ? '+' : '-';
-    my $case_stmt = "CASE $position_column \n".
-                    "  WHEN $from_position THEN $to_position\n".
-                    "  ELSE $position_column $op 1\n".
-                    "END";
-    $rs->update({ $position_column => \$case_stmt });
-    $self->store_column( $position_column => $to_position );
+    $rs->update({ $position_column => \"$position_column $op 1" });
+    $self->update({ $position_column => $to_position });
     return 1;
 }
 
@@ -353,6 +351,15 @@ __END__
 
 =head1 BUGS
 
+=head2 Unique Constraints
+
+Unique indexes and constraints on the position column are not 
+supported at this time.  It would be make sense to support them, 
+but there are some unexpected database issues that make this 
+hard to do.  The main problem from the author's view is that 
+SQLite (the DB engine that we use for testing) does not support 
+ORDER BY on updates.
+
 =head2 Race Condition on Insert
 
 If a position is not specified for an insert than a position 
@@ -369,7 +376,7 @@ you've pre-loaded the objects then when you move one of the objects
 the position of the other object will not reflect their new value 
 until you reload them from the database.
 
-The are times when you will want to move objects as groups, such 
+There are times when you will want to move objects as groups, such 
 as changeing the parent of several objects at once - this directly 
 conflicts with this problem.  One solution is for us to write a 
 ResultSet class that supports a parent() method, for example.  Another