Re: [HACKERS] WIP: Aggregation push-down

On Mon, Jan 29, 2018 at 3:32 AM, Antonin Houska <ah(at)cybertec(dot)at> wrote:
> I think of a variant of this: implement an universal function that tests the
> binary values for equality (besides the actual arguments, caller would have to
> pass info like typlen, typalign, typbyval for each argument, and cache these
> for repeated calls) and set pg_proc(oprcode) to 0 wherever this function is
> sufficient. Thus the problematic cases like numeric, citext, etc. would be
> detected by their non-zero oprcode.

I don't think that's a good option, because we don't want int4eq to
have to go through a code path that has branches to support varlenas
and cstrings. Andres is busy trying to speed up expression evaluation
by removing unnecessary code branches; adding new ones would be
undoing that valuable work.

--
Robert Haas
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