题解 | #每类试卷得分前3名#

1. 抄别人的代码实现了我自己的东西。

select tag,
       uid,
       ranking 
    from (
    select EI.tag,
           ER.uid,
           max(ER.score) max_score,
           min(ER.score) min_score,
           row_number() over(partition by EI.tag order by max(ER.score) desc,min(ER.score) desc,ER.uid desc) ranking 
      from exam_record ER 
      left join examination_info EI on ER.exam_id = EI.exam_id 
      group by EI.tag,ER.uid 
) t where ranking <= 3 ;