我就不信我找不到实习

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题解 | #查看不同年龄段的用户明细#

SELECT device_id,gender, (CASE WHEN age < 20 THEN '20岁以下' WHEN age BETWEEN 20 and 24 THEN '20-24岁' WHEN age>=25 THEN '25岁及以上' ELSE '其他' END) AS ...

Mysql

2022-01-14

0 198

题解 | #浙江大学用户题目回答情况#

SELECT university ,COUNT(q.question_id)/COUNT(DISTINCT u.device_id)FROM user_profile AS u JOIN question_practice_detail AS q ON u.device_id=q.device_i...

Mysql

2022-01-13

0 226

题解 | #浙江大学用户题目回答情况#

select device_id,question_id,result from question_practice_detail WHERE device_id IN (SELECT device_id FROM user_profile where university = '浙江大学')

Mysql

2022-01-13

0 212