Re: Finding uniques across a big join

On Wed, Nov 30, 2005 at 20:44:30 -0500,
  "John D. Burger"  wrote:
> 
> That changes the semantics of what I want.  If I group by personID 
> above, then every FOUR-way combo is of course unique.  What I'd like to 
> do is group by the three attributes, and select for personID as well.  
> But of course you can't select for columns you haven't grouped by.

Assuming that personID is an ordered type, you can select max(personID)
in the GROUP BY and save the join at the end.