题解 | #浙江大学用户题目回答情况#

select qpd.device_id,qpd.question_id,qpd.result from question_practice_detail as qpd inner join user_profile as up on up.device_id=qpd.device_id and up.university='浙江大学'

select qpd.device_id,qpd.question_id,qpd.result from question_practice_detail as qpd inner join user_profile as up on qpd.device_id=up.device_id and up.university='浙江大学'

注意顺序：A inner join B on B.=A.而不是A inner join B on A.=B.