Currency Calculator Advance Filter

1064: SELECT count(*) as total_row FROM productcategories brd INNER JOIN products ON brd.id=products.category LEFT JOIN category ON brd.pc=category.id WHERE (brd.showbrand=1) || (brd.showbrand=3) AND (brd.pc=) GROUP BY brd.id order by brd.sorting asc
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ') GROUP BY brd.id order by brd.sorting asc' at line 4