David Rowley <dgrowleyml@gmail.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.
regards, tom lane