题解 | #统计每个用户的平均刷题数#
统计每个用户的平均刷题数
https://www.nowcoder.com/practice/f4714f7529404679b7f8909c96299ac4
SELECT university, difficult_level, COUNT(b.question_id)/COUNT(DISTINCT b.device_id) AS avg_answer_cnt FROM user_profile a JOIN question_practice_detail b ON a.device_id=b.device_id JOIN question_detail c ON b.question_id= c.question_id WHERE university='山东大学' GROUP BY difficult_level
现在学院本想就业好一点四年至少得高三模式两年
加油吧
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