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(distinct d.user_id))/count(distinct c.user_id) ,3) as p from login c left join ( select a.user_id, client_id, date, first_day, second_day from login a, ( select user_id, min(date) as first_day, date_add(min(date), interval 1 day) as second_day from login group by user_id ) b where a.user_id = b.user_id and a.date = b.second_day ) d on c.user_id = d.user_id