Feature 1255 : improve sql

Replace in queries LIMIT N,M by LIMIT N OFFSET M

git-svn-id: http://piwigo.org/svn/trunk@4331 68402e56-0260-453c-a942-63ccdbb3a9ee

include/picture_comment.inc.php

@@ -136,7 +136,7 @@ SELECT com.id,author,author_id,'.$conf['user_fields']['username'].' AS username,
   WHERE image_id = '.$page['image_id'].
 $validated_clause.'
   ORDER BY date ASC
-  LIMIT '.$page['start'].', '.$conf['nb_comment_page'].'
+  LIMIT '.$page['start'].' OFFSET '.$conf['nb_comment_page'].'
 ;';
     $result = pwg_query( $query );