CREATE PROCEDURE get_all_parents (IN starting_id)
BEGIN
CREATE TEMPORARY TABLE tmp (id INT UNIQUE);
SET @id:=starting_id;
SET @done:=0;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET @done:=1;
DECLARE CONTINUE HANDLER FOR SQLSTATE '23000' SET @done:=1;
WHILE NOT @done
    INSERT INTO tmp VALUES (@id);
    SELECT parent_id INTO @id WHERE id=@id;
END WHILE
SELECT id FROM tmp
DROP TEMPORARY TABLE tmp;
END