题解 | #获得积分最多的人(二)#

select
	g.user_id,
	u.name,
	g.grade_num
from
	(
	select
		user_id, sum(grade_num) grade_num
	from
		`grade_info`
	group by
		user_id)g
left join `user` u on
	g.user_id = u.id
where
	g.grade_num = (
	select
		max(grade_num)
	from
		(
		select
			user_id, sum(grade_num) grade_num
		from
			`grade_info`
		group by
			user_id)s)
order by
	g.user_id