Re: FailedAssertion("pd_idx == pinfo->nparts", File: "execPartition.c", Line: 1689)

Andy Fan <zhihui(dot)fan1213(at)gmail(dot)com> writes:
> Attached is the v2 patch.

Forgot to mention that I'd envisioned adding this as a src/test/modules/
module; contrib/ is for things that we intend to expose to users, which
I think this isn't.

I played around with this and got the isolation test I'd experimented
with yesterday to work with it. If you revert 7a980dfc6 then the
attached patch will expose that bug. Interestingly, I had to add an
explicit AcceptInvalidationMessages() call to reproduce the bug; so
apparently we do none of those between planning and execution in the
ordinary query code path. Arguably, that means we're testing a scenario
somewhat different from what can happen in live databases, but I think
it's OK. Amit's recipe for reproducing the bug works because there are
other relation lock acquisitions (and hence AcceptInvalidationMessages
calls) later in planning than where he asked us to wait. So this
effectively tests a scenario where a very late A.I.M. call within the
planner detects an inval event for some already-planned relation, and
that seems like a valid-enough scenario.

Anyway, attached find a reviewed version of your patch plus a test
scenario contributed by me (I was too lazy to split it into two
patches). Barring objections, I'll push this tomorrow or so.

(BTW, I checked and found that this test does *not* expose the problems
with Amit's original patch. Not sure if it's worth trying to finagle
it so it does.)

regards, tom lane