Question

I want to write a SQL that returns multiple columns with a select max on one of them.
Let me clearify with an example.

Practically I’d like to have something like this:

Select max(from_date)
      ,func_status_code
      ,name
from table
where from_date <= current date

So what I want is to perform a select max on a column but also get the other columns for that row/those rows.

from_date   func_status_code   name
2012-08-21        1             A
2012-08-21        4             A
2012-08-20        5             A
2012-08-20        3             A

returning

from_date   func_status_code   name
2012-08-21        1             A
2012-08-21        4             A

I know I could do a subselect, something like:

select from_date
      ,func_status_code
      ,name
  from table
  where from_date = (Select max(from_date)
                       from table
                       where from_date <= current date
                    )           

But I can’t understand why the other method doesn’t work.
Does anybody know how to achieve this?

Answer 1

One way you can do this is with window/analytic functions:

select func_status_code, name
from (Select func_status_code, name,
             max(from_date) over () as maxdate
      from table 
      where from_date <= current date
     ) t
where from_date = maxdate