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)
http://www.nowcoder.com/practice/16d41af206cd4066a06a3a0aa585ad3d
select ROUND(count(distinct user_id)*1.0/(SELECT count(distinct user_id) from login),3)
from login
where (user_id,date)
IN
(select user_id,DATE_ADD(min(date),INTERVAL 1 DAY) from login group by user_id)
