name varchar(25) NOT NULL, `last_update` timestamp,
PRIMARY KEY ( category_id ));
film_category表
字段
说明
film_id
电影id
category_id
电影分类id
last_update
电影id和分类id对应关系的最后更新时间
CREATE TABLE film_category (
film_id smallint(5) NOT NULL,
category_id tinyint(3) NOT NULL, `last_update` timestamp);
SELECT c.name, COUNT(f.film_id) AS amount
FROM film AS f, film_category AS fc, category AS c,
(SELECT category_id FROM film_category GROUPBY category_id HAVINGCOUNT(category_id) >=5) AS cc
WHERE f.description LIKE‘%robot%‘AND f.film_id = fc.film_id
AND fc.category_id = c.category_id
AND c.category_id = cc.category_id