| From: | David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> |
|---|---|
| To: | Andreas Seltenreich <seltenreich(at)gmx(dot)de> |
| Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com> |
| Subject: | Re: Performance issue in foreign-key-aware join estimation |
| Date: | 2019-07-21 13:50:35 |
| Message-ID: | CAKJS1f8hwUK=K3TWp-CuKCsLJa=3EUq-vx+RjngVDCnmWdjE9g@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Mon, 22 Jul 2019 at 00:44, Andreas Seltenreich <seltenreich(at)gmx(dot)de> wrote:
> sqlsmith triggers an assertion in this commit (3373c7155350):
>
> TRAP: FailedAssertion("!(rel->reloptkind == RELOPT_BASEREL)", File: "equivclass.c", Line: 764)
Thanks for the report.
It looks like this is caused by the join removal code removing the
LEFT JOIN and leaving a dead rel in the eclasses ec_relids. The fix
is likely either to adjust the Assert to allow that or to add an if
test so that we only bother calling bms_add_member for base rels. I'm
not quite sure yet.
--
David Rowley http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tom Lane | 2019-07-21 14:45:32 | Re: POC: converting Lists into arrays |
| Previous Message | Michael Paquier | 2019-07-21 13:47:31 | Re: Compiler warnings with MinGW |