select `c`.`id` AS `ID`,`c`.`name` AS `Nazwa`,`g`.`amount` AS `Ilość` from (`library`.`category` `c` left join (select sum(`library`.`games`.`amount`) AS `amount`,`library`.`games`.`category_id` AS `category_id` from `library`.`games` group by `library`.`games`.`category_id`) `g` on((`g`.`category_id` = `c`.`id`)))