select u.device_id
,u.university
,ifnull(count(q.question_id),0) question_cnt
,ifnull(sum(case when q.result='wrong' then 0 else 1 end),0) right_question_cnt
from user_profile as u
left join question_practice_detail as q
on u.device_id=q.device_id  and month(q.date)=8
where u.university = '复旦大学' 
group by u.device_id