Re: Parallel Append subplan order instability on aye-aye

On Mon, May 20, 2019 at 4:46 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
> > Here's a one-off regression test failure of a sort that commit
> > 624e440a intended to fix.
>
> Note that in the discussion that led up to 624e440a, we never did
> think that we'd completely explained the original irreproducible
> failure.
>
> I think I've seen a couple of other cases of this same failure
> in the buildfarm recently, but too tired to go looking right now.

I think it might be dependent on incidental vacuum/analyze activity
having updated reltuples. With the attached script, I get the two
plan variants depending on whether I comment out "analyze a_star". I
guess we should explicitly analyze these X_star tables somewhere?

--
Thomas Munro
https://enterprisedb.com