Re: [PATCH] Negative Transition Aggregate Functions (WIP)

On Mon, Dec 16, 2013 at 08:39:33PM +1300, David Rowley wrote:
> On Mon, Dec 16, 2013 at 6:00 AM, Ants Aasma <ants(dot)aasma(at)eesti(dot)ee> wrote:
>
> > On Dec 15, 2013 6:44 PM, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > > David Rowley <dgrowleyml(at)gmail(dot)com> writes:
> > > > I've attached an updated patch which includes some documentation.
> > > > I've also added support for negfunc in CREATE AGGREGATE. Hopefully
> > that's
> > > > an ok name for the option, but if anyone has any better ideas please
> > let
> > > > them be known.
> > >
> > > I'd be a bit inclined to build the terminology around "reverse" instead
> > of
> > > "negative" --- the latter seems a bit too arithmetic-centric. But that's
> > > just MHO.
> >
> > To contribute to the bike shedding, inverse is often used in similar
> > contexts.
> >
> I guess it's not really bike shedding, most of the work I hope is done, so
> I might as well try to get the docs polished up and we'd need a consensus
> on what we're going to call them before I can get that done.
>
> I like both of these better than negative transition function and I agree
> negative implies arithmetic rather than opposite.
> Out of these 2 I do think inverse fits better than reverse, so I guess that
> would make it "inverse aggregate transition function".
> Would that make the CREATE AGGREGATE option be INVFUNC ?
>
> Any other ideas or +1's for any of the existing ones?

+1 for inverse.

Cheers,
David.
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