题解 | #统计每个学校的答过题的用户的平均答题数#
统计每个学校的答过题的用户的平均答题数
https://www.nowcoder.com/practice/88aa923a9a674253b861a8fa56bac8e5
select university,count(qpd.question_id)/count(distinct qpd.device_id)as avg_answer_cut from user_profile up join question_practice_detail qpd on up.device_id = qpd.device_id group by university
