题解 | #统计复旦用户8月练题情况#
统计复旦用户8月练题情况
https://www.nowcoder.com/practice/53235096538a456b9220fce120c062b3
select a.device_id, a.university, count(question_id),count(CASE WHEN b.result = 'right' THEN 1 END) from user_profile a left join question_practice_detail b on a.device_id = b.device_id and month(date) = 8 where a.university = '复旦大学' group by a.device_id;
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