Re: ALTER TABLE lock downgrades have broken pg_upgrade

On Tue, May  3, 2016 at 12:07:51PM -0400, Tom Lane wrote:
> I think possibly the easiest fix for this is to have pg_upgrade,
> instead of RESETting a nonexistent option, RESET something that's
> still considered to require AccessExclusiveLock.  "user_catalog_table"
> would work, looks like; though I'd want to annotate its entry in
> reloptions.c to warn people away from downgrading its lock level.
> 
> More generally, though, I wonder how we can have some test coverage
> on such cases going forward.  Is the patch below too ugly to commit
> permanently, and if so, what other idea can you suggest?

FYI, I only test _supported_ version combinations for pg_upgrade, i.e. I
don't test pg_upgrade _from_ unsupported versions, though I can see why
maybe I should.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com

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