On fre, 2009-08-21 at 20:07 -0400, Tom Lane wrote:
> As of SQL99 it's supposed to be legal if you're grouping by a primary key
> (or some other cases where the other columns can be proved functionally
> dependent on the grouping columns, but that's the most useful one).
> We haven't got round to implementing that, but I'm not sure that it
> would make the Drupal code work anyway. Are they actually writing to
> spec here, or just doing whatever mysql will let them?
>
> BTW, I was under the impression there already *was* a TODO entry about
> improving our standards compliance in this area. I can't find it in
> the list right now, though.
I added "Add support for functional dependencies" just now, with a
comment how this relates to GROUP BY.