题解 | #浙大不同难度题目的正确率#
浙大不同难度题目的正确率
https://www.nowcoder.com/practice/d8a4f7b1ded04948b5435a45f03ead8c
select n.difficult_level, sum(if(n.result = "right",1,0))/count(n.result) as correct_rate from (select c.difficult_level,b.result from user_profile a ,question_practice_detail b,question_detail c where a.device_id = b.device_id and b.question_id = c.question_id and a.university = "浙江大学") n group by n.difficult_level order by correct_rate
学而思开奖50人在聊
