select c.name,coun
from film f inner join film_category fc on f.film_id==fc.film_id
inner join category c on c.category_id==fc.category_id,/将三个表连接起来/
( select name,count(f.film_id) coun/查找出含有robot的电影的分类和含有robot的电影数目/
from film f inner join film_category fc on f.film_id==fc.film_id
inner join category c on c.category_id==fc.category_id
where f.description like '%robot%'
group by c.name
) s
where s.name==c.name
group by c.name
having count(f.film_id)>=5