Re: proposal: tuplestore, tuplesort aggregate functions

On Wed, Aug 18, 2010 at 10:39:33AM -0400, Tom Lane wrote:
> David Fetter <david(at)fetter(dot)org> writes:
> > Apart from the medians, which "median-like" aggregates do you have in
> > mind to start with? If you can provide examples of "median-like"
> > aggregates that people might need to implement as user-defined
> > aggregates, or other places where people would use this machinery, it
> > will make your case stronger for this refactoring.
>
> There would be plenty of scope to re-use the machinery without any
> SQL-level extensions. All you need is a polymorphic aggregate
> transition function that maintains a tuplestore or whatever.
> I don't see that extra syntax in CREATE AGGREGATE is really buying
> much of anything.

Thanks for clarifying. Might this help out with things like GROUPING
SETS or wCTEs?

Cheers,
David (a little slow today).
--
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