题解 | #统计每个学校各难度的用户平均刷题数#
统计每个学校各难度的用户平均刷题数
http://www.nowcoder.com/practice/5400df085a034f88b2e17941ab338ee8
select university,difficult_level,round(count(*)/count(distinct qpd.device_id),4) avg_answer_cnt
from question_detail qd,question_practice_detail qpd,user_profile up
where qd.question_id=qpd.question_id and qpd.device_id=up.device_id
group by university,difficult_level
from question_detail qd,question_practice_detail qpd,user_profile up
where qd.question_id=qpd.question_id and qpd.device_id=up.device_id
group by university,difficult_level
投递牛客等公司10个岗位
速腾聚创二面26人在聊