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,
round(count(q.result) / count(distinct q.device_id), 4) as avg_answer_cnt
from
user_profile u
JOIN question_practice_detail q
WHERE
u.device_id = q.device_id
GROUP BY
university;
