Re: [HACKERS] Implement targetlist SRFs using ROWS FROM() (wasChanged SRF in targetlist handling)

On Tue, Jan 17, 2017 at 1:18 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Andres Freund <andres@anarazel.de> writes:
>> I'd not have gone for SetResult if we didn't already have Result.  I'm
>> not super happy ending up having Project in ProjectSet but not in the
>> Result that end up doing the majority of the projection.  But eh, we can
>> live with it.
>
> Using Result for two completely different things is a wart though.  If we
> had it to do over I think we'd define Result as a scan node that produces
> rows from no input, and create a separate Project node for the case of
> projecting from input tuples.  People are used to seeing Result in EXPLAIN
> output, so it's not worth the trouble of changing that IMO, but we don't
> have to use it as a model for more node types.

+1, although I think changing the existing node would be fine too if
somebody wanted to do the work.  It's not worth having that wart
forever just to avoid whatever minor pain-of-adjustment might be
involved.

-- 
Robert Haas
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