select a.title, a.description
from(select fc.category_id,c.name,film.title, film.description
from film, film_category fc,category c
where fc.film_id=film.film_id
and c.category_id=fc.category_id) a
where a.name="Action"

这道题的思路就是先自己建立一个大表，再从大表里面提取，写代码的时候可以先从括号里面的内容写起