Thread

Re: Bug in ALTER SUBSCRIPTION ... SERVER / ... CONNECTION with broken old server

Jeff Davis <pgsql@j-davis.com> — 2026-05-09T01:01:28Z

On Wed, 2026-05-06 at 15:57 +0800, Chao Li wrote:
> PFA v3 - addressed Ajin and Zsolt’s comments.

Thank you for the report!

The proposed patch seems unnecessarily complex, though. It seems too
easy to add GetSubscriptionConninfo() in the wrong place and end up
with another problem that's not easily detected.

Can't we just do something like the attached? It's easy to explain at
the call site that, when changing to a different server or using
CONNECTION instead, that we don't need the old conninfo at all.

I included your test case in my patch, and it passes.

Also, Hayato Kuroda's report was an issue also because the error could
be thrown even if slotname was NULL. Patch attached for that, as well.
Thank you, also!

Regards,
	Jeff Davis