php - mysql3表查询

Question

【star明星表】
id name
有N多明星，自增id
【sing歌曲表】
id name star_id
N多歌曲
【movie电影表】
id name star_id
N多电影

查询每个明星一共有多少歌曲多少电影
name cout_sing count_movie

Answer 1

select conut(tb1.id) as singnum
from star as tb3
left join sing as tb1 on tb1.starid=tb3.id
where tb3.id=somenoe

Answer 2

select a.name,count(b.id) as singnum,count(c.id) as movienum
from star as a
left join sing as b on a.id=b.star_id left join movie as c on c.star_id=a.id group by b.id,c.id.