Not fully sure on the syntax of the Window to accomplish the specified goal - and am not sure it would be any cleaner anyway.
But, the reason I am responding is how you phrased "...windows only compared groups of records in the same table". When I say: FROM tableA * JOIN tableB I have now effectively created a new "table" in the sense that anything I can do on tableA or tableB I can also do on the result of the joining of those two tables. Re-reading the comment and context it probably would be more fair to guess that you know this. In the context of a Window function you can use it AFTER you perform a LEFT JOIN - but you may not need to do the "SELECT id, count(*) GROUP BY id" on the child table but instead can just do a direct left join onto child and use a Window. Again, mostly just speculation and for the moment I don't have the time to spare to try out a Window based solution; especially since my gut says the LEFT JOIN on the grouped child is likely the best solution anyway. David J. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Mike Orr Sent: Thursday, March 31, 2011 3:20 PM To: [email protected] Subject: Re: [GENERAL] Counting records in a child table Thanks. How would I do it with a window function? I thought windows only compared groups of records in the same table. -- Sent via pgsql-general mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
