Re: [PATCH] Doc: document standard_conforming_strings dump/restore incompatibility

On Wed, Jun 17, 2026 at 01:29:09PM -0400, Tom Lane wrote:
> Baji Shaik <baji(dot)pgdev(at)gmail(dot)com> writes:
> > Commit 45762084 [1] forced standard_conforming_strings to always be ON in
> > PostgreSQL 19. The release notes mention this change, but neither the
> > pg_dump/pg_restore reference pages nor the migration section note the
> > implications for restoring older dump files.
>
> Okay, that's an oversight in the release notes for sure. I'm more
> skeptical about putting such information into the application
> reference pages though. It seems of only transient interest, but
> any text we put there is likely to survive for many years.
>
> Independently of that...
>
> > The attached patch adds notes to:
> > - pg_dump reference page (Notes section)
> > - pg_restore reference page (Notes section)
> > - release-19 migration section
>
> I don't like this patch, because it presents much too rosy a view of
> whether you can get away with not re-taking the dump. It's unsafe
> even with COPY-format data, because string literals in views, table
> default expressions and constraints, function definitions, etc are all
> at hazard of being misinterpreted. I think we should just say it
> won't work correctly, full stop.
>
> I'm inclined to do more or less the attached, which also fixes what
> seems a thinko in the existing text: we should say that clients still
> support standard_conforming_strings = off, not
> escape_string_warning = off.

I have applied a slightly modified version to master, attached. The git
commit suggested this problem, but I didn't understand the impact at the
time I read it.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

Do not let urgent matters crowd out time for investment in the future.