Re: WITHIN GROUP patch

Atri Sharma <atri(dot)jiit(at)gmail(dot)com> writes:
> Please find attached the latest patch for WITHIN GROUP. This patch is
> after fixing the merge conflicts.

I've started to look at this patch now. I have a couple of immediate
reactions to the catalog changes:

1. I really hate the way you've overloaded the transvalue to do something
that has approximately nothing to do with transition state (and haven't
updated catalogs.sgml to explain that, either). Seems like it'd be
cleaner to just hardwire a bool column that distinguishes regular and
hypothetical input rows. And why do you need aggtranssortop for that?
I fail to see the point of sorting on the flag column.

2 I also don't care for the definition of aggordnargs, which is the number
of direct arguments to an ordered set function, except when it isn't.
Rather than overloading it to be both a count and a couple of flags,
I wonder whether we shouldn't expand aggisordsetfunc to be a three-way
"aggregate kind" field (ordinary agg, ordered set, or hypothetical set
function).

regards, tom lane