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 p.device_id,p.university,
sum(if(q.result is not null,1,0)) as question_cnt,
sum(if(q.result = "right",1,0)) as right_question_cnt
from user_profile p
left join question_practice_detail q on p.device_id = q.device_id
and month(q.date) = "08"
where p.university = "复旦大学"
group by p.device_id;
