select t.id, t.name, t.grade_num from( select u.id, u.name, a.grade_num, DENSE_RANK() over (order by a.grade_num desc) as ranking from user u join ( select user_id, sum(grade_num) as grade_num from grade_info group by user_id ) a on u.id= a.user_id) t where t.ranking = 1