SELECT DISTINCT(schoenmaat) as schoenmaat FROM stock WHERE productID IN () AND schoenmaat != 0 AND verwijderd = '0' AND actief = '1' ORDER BY schoenmaat ASC - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') AND schoenmaat != 0 AND verwijderd = '0' AND actief = '1' ORDER BY schoenmaat ' at line 1