题解 | #每篇文章同一时刻最大在看人数#
每篇文章同一时刻最大在看人数
https://www.nowcoder.com/practice/fe24c93008b84e9592b35faa15755e48
with t as (
select artical_id,in_time as dt,1 diff
from tb_user_log
where artical_id != 0
union all
select artical_id,out_time as dt,-1 diff
from tb_user_log
where artical_id != 0
),
t1 as (
select artical_id,sum(diff) over(partition by artical_id order by dt rows between unbounded preceding and current row) as dd
from t
)
select artical_id,max(dd) as max_uv
from t1
group by artical_id
order by max_uv desc
