select device_id ,university ,sum(if_cnt) question_cnt ,sum(right_cnt) right_question_cnt from (select a.device_id ,a.university ,if(b.result='right',1,0) right_cnt ,if(IFNULL(MONTH(b.date), 0) = 8,1,0) if_cnt from user_profile a left join question_practice_detail b on a.device_id=b.device_id where ...