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 difficult_level,sum(if(result='right',1,0))/count(q.question_id)correct_rate from question_practice_detail q join user_profile u on u.device_id=q.device_id join question_detail qd on q.question_id=qd.question_id where university='浙江大学' group by qd.difficult_level order by correct_rate