题解 | 浙大不同难度题目的正确率
select
qd.difficult_level as diffcult_level,
sum(
case
when qp.result = 'right' then 1
else 0
end
) / count(qp.question_id) as correct_rate
from
user_profile u
inner join question_practice_detail qp on u.device_id = qp.device_id
inner join question_detail qd on qp.question_id = qd.question_id
where
u.university = '浙江大学'
group by
qd.difficult_level
order by correct_rate
查看13道真题和解析