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
select artical_id, max(sum_uv) max_uv from( select artical_id, sum(flag)over(partition by artical_id order by td,flag desc) sum_uv from( select artical_id,in_time td,1 flag from tb_user_log where artical_id<>0 union all select artical_id,out_time, -1 flag from tb_user_log where artical_id<>0 )t1 )t2 group by artical_id order by max_uv desc