Out of memory (Needed 16777188 bytes) SQL=SELECT a.id AS value, a.title AS text, COUNT(DISTINCT b.id) AS level, a.parent_id FROM xxxxx_usergroups AS a LEFT JOIN `xxxxx_usergroups` AS b ON a.lft > b.lft AND a.rgt < b.rgt GROUP BY a.id, a.title, a.lft, a.rgt, a.parent_id ORDER BY a.lft ASC