题解 | #牛客每个人最近的登录日期(四)#
牛客每个人最近的登录日期(四)
https://www.nowcoder.com/practice/e524dc7450234395aa21c75303a42b0a
可以使用row开窗函数
select date,count(case when num = 1 then 1 else null end) from (
select
*,
row_number() over(partition by l1.user_id order by l1.date) as num
from login l1
)w1
group by date