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