题解 | #牛客每个人最近的登录日期(三)#
牛客每个人最近的登录日期(三)
https://www.nowcoder.com/practice/16d41af206cd4066a06a3a0aa585ad3d
select round(count(login.date)/count(1),3) from( select user_id,min(date) date from login group by user_id )t1 left join login on t1.user_id = login.user_id and datediff(t1.date,login.date)=-1