题解 | 获得积分最多的人(一)

select name, grade_num from(
select name, row_number() over (order by grade_num desc) as rk,grade_num
from(
    select u.id,u.name,sum(g.grade_num) over(partition by g.user_id) as grade_num
    from user u
    join grade_info g
    on u.id = g.user_id
)a)b
where rk=1

思路：先算每个用户的累计得分，再对累计得分进行排名，再取出排名第一的