Re: Oversight in reparameterize_path_by_child leading to executor crash

Richard Guo <guofenglinux@gmail.com>

From: Richard Guo <guofenglinux@gmail.com>

To: Alena Rybakina <lena.ribackina@yandex.ru>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Andrei Lepikhov <a.lepikhov@postgrespro.ru>

Date: 2023-12-06T07:30:22Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Postpone reparameterization of paths until create_plan().
- b7e2121ab7d6 17.0 landed
Apply band-aid fix for an oversight in reparameterize_path_by_child.
- e031995d5c26 14.11 landed
- 7af96a66f43c 13.14 landed
- 62f120203147 16.2 landed
- 2e822a1d62d0 12.18 landed
- 12ec16d11c8b 15.6 landed

I've self-reviewed this patch again and I think it's now in a
committable state.  I'm wondering if we can mark it as 'Ready for
Committer' now, or we need more review comments/feedbacks.

To recap, this patch postpones reparameterization of paths until
createplan.c, which would help avoid building the reparameterized
expressions we might not use.  More importantly, it makes it possible to
modify the expressions in RTEs (e.g. tablesample) and in RelOptInfos
(e.g. baserestrictinfo) for reparameterization.  Failing to do that can
lead to executor crashes, wrong results, or planning errors, as we have
already seen.

Thanks
Richard