DELIMITER ;;
CREATE DEFINER=`webdev`@`localhost` PROCEDURE `update_tree`(IN _pageID INT)
BEGIN

DECLARE done INT DEFAULT FALSE;
DECLARE _id INT;

DECLARE curs CURSOR FOR SELECT DISTINCT(descendant) FROM PageClosure WHERE ancestor = _pageID OR descendant = _pageID;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;



OPEN curs;

REPEAT
FETCH curs INTO _id;

IF ! done THEN

UPDATE PageClosure t
JOIN (SELECT c.descendant, COUNT(c.ancestor) -1 AS `depth` FROM PageClosure c GROUP BY c.descendant ) AS d ON (d.descendant = t.descendant)
SET t.`depth` = d.`depth`
WHERE t.descendant = _id;


END IF;
UNTIL done END REPEAT;

CLOSE curs;
END;;
DELIMITER ;