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