Remove duplicate item menu links in Drupal.

remove_duplicate_menu_links.sql

DELETE FROM menu_links WHERE mlid IN (
	SELECT duped_ids.mlid FROM (
		SELECT max(mlid) AS mlid, menu_name, link_title, link_path, router_path, module, count(*) 
		FROM menu_links GROUP BY menu_name, link_title, link_path, router_path HAVING (count(*) > 1)) AS duped_ids);