Почему выпадает ошибка Duplicate column name 'id'?

делаю запрос

SELECT COUNT(*) 
FROM (
    SELECT 
    `fl_serial`.`id`,
    `fl_serial`.`name_serial`,
    `fl_serial`.`slug_serial`,
    `fl_serial`.`description_serial`,
    `fl_serial`.`nesting`,
    `fl_serial`.`year`,
    `fl_serial`.`country_title`,
    `fl_film`.`id`,
    `fl_film`.`name_film`,
    `fl_film`.`slug_film`,
    `fl_film`.`description_film`,
    `fl_film`.`nesting`,
    `fl_film`.`year`,
    `fl_film`.`country_title`,
    `fl_mfilm`.`id`,
    `fl_mfilm`.`name_mfilm`,
    `fl_mfilm`.`slug_mfilm`,
    `fl_mfilm`.`description_mfilm`,
    `fl_mfilm`.`nesting`,
    `fl_mfilm`.`year`,
    `fl_mfilm`.`country_title`,
    `fl_cat_serial`.`id`,
        COALESCE(`fl_serial`.`id`, `fl_film`.`id`, `fl_mfilm`.`id` ) AS `ids`,
        COALESCE(`fl_serial`.`name_serial`, `fl_film`.`name_film`, `fl_mfilm`.`name_mfilm` ) AS `name`,
        COALESCE(`fl_serial`.`slug_serial`, `fl_film`.`slug_film`, `fl_mfilm`.`slug_mfilm`) AS `slug`,
        COALESCE(`fl_serial`.`description_serial`, `fl_film`.`description_film`, `fl_mfilm`.`description_mfilm`) AS `description`,
        COALESCE(`fl_serial`.`nesting`, `fl_film`.`nesting`, `fl_mfilm`.`nesting` ) AS `nesting`,
        COALESCE(`fl_serial`.`year`, `fl_film`.`year`, `fl_mfilm`.`year` ) AS `years`,
        COALESCE(`fl_serial`.`country_title`, `fl_film`.`country_title`, `fl_mfilm`.`country_title` ) AS `country_title` 
        FROM `fl_cat_serial` 
        LEFT JOIN `fl_serial` ON fl_cat_serial.id_serial = fl_serial.id 
        LEFT JOIN `fl_film` ON fl_cat_serial.id_film = fl_film.id 
        LEFT JOIN `fl_mfilm` ON fl_cat_serial.id_mfilm = fl_mfilm.id 
        WHERE `fl_cat_serial`.`id_cat`=12 
        GROUP BY `ids`) `c` 

получаю следующую ошибку

#1060 - Duplicate column name 'id'

почему