On Tue, Apr 19, 2011 at 10:47 AM, Uwe Bartels <uwe.bart...@gmail.com> wrote: > Oh, I do care about these columns. > But by using an group by on the key columns, I cannot select the columns as > they are. Otherwise you get an error message. > So I have to use an aggregate functionlike min().
I find that slightly contradictory: either you do care about the values then your business requirements dictate the aggregate function. If you only want to pick any value actually in the table but do not care about which one (e.g. MIN or MAX or any other) then you don't actually care about the value. Because "SELECT a, MAX(b) ... GROUP BY a" and "SELECT a, MIN(b) ... GROUP BY a" are not equivalent. And, if you do not care then there is probably no point in selecting them at all. At best you could use a constant for any legal value then. Cheers robert -- remember.guy do |as, often| as.you_can - without end http://blog.rubybestpractices.com/ -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
