SQL Server: how to imitate oracle keep dense_rank query?

Question

I have an Oracle query

select max(m.id),
       m.someId keep (DENSE_RANK FIRST ORDER BY m.UpdateDate desc) 
from MyTable m 
groupBy m.someId

Answer 1

SQL Server does not support the "keep" construct, so you need to use a subquery:

select m.*
from (select *, row_number() over (partition by m.someid ORDER BY m.UpdateDate desc) as seqnum
      from MyTable m
     ) m
where seqnum = 1

This finds the first row for each m.id with the most recent UpdateDate. It then chooses that row in the outer query. Note that you don't need a group by with this method.