题解 | #获取所有非manager员工当前的薪水情况#
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/practice/2f2e556d335d469f96b91b212c4c203e
连结 film 和 film_category两表，用标量子查询得到 “Action” 作为连接表中category_id的限制
select f.title,f.description from film_category as fc left join film as f on fc.film_id = f.film_id where fc.category_id = (select category_id from category where name = 'Action');
