join大法
使用子查询的方式找出属于Action分类的所有电影对应的title,description
http://www.nowcoder.com/questionTerminal/2f2e556d335d469f96b91b212c4c203e
select title,description from ( select ff.title,ff.description,c.name from film_category fc join film ff on fc.film_id=ff.film_id join category c on fc.category_id =c.category_id ) f where f.name='Action';