题解 | #每类试卷得分前3名#

select * from
(
SELECT tag as tid,uid,
ROW_NUMBER() over(partition by tag ORDER BY max(score) desc,min(score) desc,uid desc ) as ranking
from  exam_record er join examination_info ei 
on er.exam_id=ei.exam_id
group by tid,uid)t
where ranking<=3;
经典题目