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 b.user_id) / count(distinct a.user_id), 3) as p
from (
select user_id, min(date) as date from login group by user_id
) a
left join login b
on a.user_id = b.user_id
and datediff(b.date, a.date) = 1