89和90 解题方法差不多吧,有点迷惑????

WITH grade_new AS (
    SELECT
       *,
    sum(gi.grade_num) OVER (PARTITION BY name) rk
FROM user
LEFT JOIN grade_info gi
ON user.id = gi.user_id
)
SELECT
    DISTINCT gn.id,gn.name,gn.rk grade_num
FROM grade_new gn
WHERE gn.rk = (SELECT max(rk) FROM grade_new)
ORDER BY gn.id