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
http://www.nowcoder.com/practice/53235096538a456b9220fce120c062b3
from user_profile up left join question_practice_detail qpd
on up.device_id=qpd.device_id
where university='复旦大学' and month(date)=8
group by up.device_id
