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
select
t1.date,
sum(if_new) as new
from
(select
l.user_id,
l.date,
case
when row_number() over(partition by l.user_id order by l.date asc)=1
then 1 else 0
end as if_new
from
login l
) t1
group by
t1.date
order by
t1.date asc
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