On Wed, Nov 19, 2008 at 08:47:57AM -0600, Scara Maccai wrote:
> CREATE TABLE mytab
> (
> num integer,
> mydate timestamp
> );
>
> and I want to find MAX(num) and the "mydate" where it first happened.
>
> I guess I could use
>
> select * from mytab where num = (select MAX(num) from mytab) order by
> mydate limit 1;
Why not just do:
SELECT * FROM mytab
ORDER BY num, mydate
LIMIT 1;
If you're trying to do more complicated things, DISTINCT ON may be more
useful.
> Do I have to write my own MAX function, something like:
>
> select MYMAX(num, timestamp) from mytab
>
> which would return a custom type? Or is there a better way?
I've wanted MAX to support this sort of thing several times before, but
alas it doesn't.
Sam