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, IF(B.question_cnt is null , 0, B.question_cnt), IF(B.right_question_cnt is null , 0,B.right_question_cnt) From user_profile A left join (select device_id,count(device_id) as question_cnt,sum(Case result when 'wrong' then 0 else 1 end ) as right_question_cnt From question_practice_detail where month(date)=8 Group By device_id ) AS B ON A.device_id=B.device_id where university ='复旦大学'
