Re: BUG #19460: FULL JOIN rewriting issue on empty queries

Thanks Tom and Richard for the quick diagnosis and fix, I should be the one
saying thanks here!

François

On Tue, Apr 21, 2026 at 1:04 AM Richard Guo <guofenglinux(at)gmail(dot)com> wrote:

> On Tue, Apr 21, 2026 at 7:40 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Ah: equivclass.c doesn't mind letting em->em_relids be an alias
> > for the left_relids or right_relids of some source RestrictInfo.
> > That's not problematic as long as those are all constants after
> > construction of the EquivalenceClass, but when remove_rel_from_eclass
> > is trying to change things, it's a big problem.
>
> ha, I just came to the same conclusion.
>
> > This seems to do the trick to fix it, although I'm going to wait
> > for a valgrind regression run to finish before deciding this
> > is enough:
>
> This seems safe enough to me. LGTM.
>
> - Richard
>