select t1.device_id,t1.university,count(t2.device_id) as question_cnt,sum(if(t2.result='right',1,0)) as right_question_cntfrom user_profile t1left joinquestion_practice_detail t2on t1.device_id=t2.device_id and month(t2.date)=8where t1.university='复旦大学'group by t1.device_id,t1.university--因为用到了查询字段和...