Re: plan shape work

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Mon, Sep 22, 2025 at 2:15 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> In the second place, we should not need to add two hundred lines
>> of new code to createplan.c to accomplish this. Why not simply
>> bms_difference the joinrel's relids from the union of the inputs'
>> relids?

> ... On the other hand, I'm not sure that I'm interpreting your remarks
> correctly. When you say "bms_difference the joinrel's relids from the
> union of the inputs' relids" maybe you're specifically talking about
> the handling of the RTE_JOIN relids, and I don't care very much how we
> account for those. So I guess I need some clarification here as to
> what your thinking is.

What I'm saying is that I'd be much happier with 0003 if it looked
about like the attached. We do not need a heap of mechanism
redundantly proving that the planner is getting these things right
(and potentially containing its own bugs).

> Note that my goal for
> this commitfest was to get 0001-0004 committed, partly because I
> wasn't too sure whether the later patches might need some adjustment.

Fair enough. I think we can reach agreement on that much pretty quickly.

regards, tom lane