Mysql SELECT inside UPDATE

Question

UPDATE forms SET

pos = (SELECT MIN(pos)-1 FROM forms)

WHERE id=$id

This doesn\'t work, error message:

**You can\'t specify target         


        

Answer 1

You could also try:

START TRANSACTION;
SET @newMin := MIN(pos)-1 FROM forms;
UPDATE forms SET pos=@newMin WHERE id='$id';
COMMIT;