Ошибка БД

Error Number: 1064

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 `category_id` IS NULL ORDER BY rand() LIMIT 2' at line 7

SELECT SQL_CALC_FOUND_ROWS p.id, p.alias, p.nice_alias, p.name_0 as name, pd.image, p.price, p.type, pd.short as short, pd.body as body, ct.name_0 as catname FROM (prod p) LEFT JOIN prod_description pd ON p.alias=pd.alias LEFT JOIN cats ct ON p.type=ct.alias WHERE `p`.`type` = 'convectors' AND `p`.`id` != AND `category_id` IS NULL ORDER BY rand() LIMIT 2