Re: WIP: Covering + unique indexes.

Hi!

> 21 марта 2018 г., в 21:51, Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> написал(а):
>
>
> I took a look at this patchset. I have some notes about it.
>
> * I see patch changes dblink, amcheck and tcl contribs. It would be nice to add corresponding
> check to dblink and amcheck regression tests. It would be good to do the same with tcn contrib.
> But tcn doesn't have regression tests at all. And it's out of scope of this patch to add regression
> tests to tcn. So, it's OK to just check that it's working correctly with covering indexes (I hope it's
> already done by other reviewers).
>
I propose attached tests to amcheck and dblink. Not very extensive tests though, but enough to keep things working.
> * I think that subscription regression tests in src/test/subscription should have some use
> of covering indexes. Logical decoding and subscription are heavily using primary keys.
> So they need to be tested to work correctly with covering indexes.
I've attached subscription tests. Unfortunately, they crash publisher with
2018-03-28 15:09:05.953 +05 [81805] 001_rep_changes.pl LOG: statement: DELETE FROM tab_cov WHERE a > 20
2018-03-28 15:09:05.954 +05 [81691] LOG: server process (PID 81805) was terminated by signal 11: Segmentation fault
Any of this commands lead to this
$node_publisher->safe_psql('postgres', "DELETE FROM tab_cov WHERE a > 20");
$node_publisher->safe_psql('postgres', "UPDATE tab_cov SET a = -a");

I didn't succeed in debugging. Maybe Anastasia can comment on is it bug or is it something wrong with tests?
>
> * I also think some isolation tests in src/test/isolation need to check covering indexes too.
> In particular insert-conflict-*.spec and lock-*.spec and probably more.
Currently, I couldn't compose good test scenarios, but I will think a bit about it more.

Best regards, Andrey Borodin.