SQL 查询过滤器按修改日期

Question

I beg your pardon for my English in advance.

I have this data:

I need to get the max process for the OP column in a given Start_date .

That should look like this:

I can't get that, any help would be appreciated

Answer 1

Toad is often used with Oracle, so I'll use Oracle syntax. You can adapt for other databases. The key is extracting the date from start_date .

select t.*
from (select t.*,
             row_number() over (partition by trunc(start_date) order by start_date desc) as seqnum
      from t
     ) t
where seqnum = 1;