题解 | #获取每个部门中当前员工薪水最高的相关信息#
查找描述信息中包含robot的电影对应的分类名称以及电影数目，而且还需要该分类对应电影数量>=5部
http://www.nowcoder.com/practice/3a303a39cc40489b99a7e1867e6507c5
select c.name, sum(case when f.description like '%robot%' then 1 end) from film f join film_category fc on f.film_id = fc.film_id join category c on fc.category_id = c.category_id group by c.name having count(*) >= 5 and sum(case when f.description like '%robot%' then 1 end) > 0
