Stored Procedure for Updating Nested Hierarchy

[CrimpJiggler]

I'm using a CRUD system which won't automatically update the lft and rght values of my hierarchical tables when I enter a new row. I don't know what the best way to solve this is, all I can think of is adding a stored procedure to the table so that whenever a new row gets added, the procedure will make sure the lft and rght values get shifted. Is this even possible with stored procedures?

[CrimpJiggler]

I can't edit my post, I wanna ask a better question. Is there a simple way to make MySQL handle nested hierarchical database tables for you. My table has a parent_id, lft and rght value. CakePHP handles this automatically but does MySQL have built in functionality for that? If not, can anyone point me towards a simple stored procedure to do it? I know what I need to do, just find out whether the parent node is empty or not, if its empty then I expand it by 2, and shift everything to the left and right of it two. If its not empty, then I just shift everything from the start of the parent node to the right. There must be an automatic way to do it though.

[CrimpJiggler]

I just made this procedure which will do for now:

DELIMITER $$
CREATE PROCEDURE rearrangeNodes(IN parentId INT)
BEGIN

	DECLARE parentLft INTEGER;
	SET parentLft = (SELECT lft FROM table WHERE category_id = NEW.parentId);

	UPDATE `table` 

	SET lft = CASE WHEN lft > parentLft THEN
		lft + 2
	ELSE
		lft + 0
	END,		
	rght = CASE WHEN rght >= parentLft THEN
		rght + 2
	ELSE
		rght + 0
	END
	WHERE  lft >= newLft;

END$$