题解 | 获得积分最多的人(二)

select b.id, b.name, b.grade_num
from 
(select a.id id, a.name name, a.grade_num grade_num, dense_rank()over(order by a.grade_num desc) d
   from 
      (select g.user_id id, u.name name,sum(grade_num) grade_num
          from user u right join grade_info g on u.id=g.user_id
          group by g.user_id, u.name
      ) a
) b
where b.d=1