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
t2.university,
count(t1.question_id) / count(distinct t1.device_id) avg_answer_cnt
from
question_practice_detail t1
join user_profile t2 on t2.device_id = t1.device_id
and t1.result is not null
group by
t2.university;
查看18道真题和解析