题解 | #每个题目和每份试卷被作答的人数和次数#
每个题目和每份试卷被作答的人数和次数
https://www.nowcoder.com/practice/203d0aed8928429a8978185d9a03babc
select * from (select exam_id as tid, count(distinct uid) as uv, count(uid) as pv from exam_record group by exam_id order by uv desc, pv desc)a union all select * from ( select question_id as tid, count(distinct uid) as uv, count(uid) as pv from practice_record group by question_id order by uv desc ,pv desc)b