Re: (P)SQL for a sum with constraints

On Wed, Apr 15, 2009 at 11:09:49AM +0100, Shug Boabby wrote:
> Anyone have any ideas how to do this? I'm able to do it
> programmatically, but it's slow. Optimally I'd like to be able to do
> this in the DB. As you can see, it's a little trickier that the usual
> aggregate function with a GROUP BY and HAVING.

this is called cumulative sum, and can be done quite easily.

check this blogpost (but also its comments! - the c function is not
necessary!)
http://www.depesz.com/index.php/2007/08/17/rownum-anyone-cumulative-sum-in-one-query/

depesz

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