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
q2.difficult_level,
sum(if (q1.result = 'right', 1, 0)) / count(q1.result)
from
user_profile u
join question_practice_detail q1 on u.device_id = q1.device_id
join question_detail q2 on q1.question_id = q2.question_id
where
u.university = '浙江大学'
group by
q2.difficult_level
order by
sum(if (q1.result = 'right', 1, 0)) / count(q1.result)
