From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeff Davis <pgsql@j-davis.com>
cc: Richard Guo <guofenglinux@gmail.com>, pgsql-bugs@postgresql.org
Subject: Re: hashing bpchar for nondeterministic collations is broken
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Comments: In-reply-to Jeff Davis <pgsql@j-davis.com>
	message dated "Fri, 02 Dec 2022 13:21:08 -0800"
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Date: Fri, 02 Dec 2022 16:49:16 -0500
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Jeff Davis <pgsql@j-davis.com> writes:
> But assuming someone does use that combination of features in 15.1, and
> we release 15.2 with my fix in it, then the consequences could be
> severe: a pg_dump with default options on their bpchar-
> nondeterministic-collation-hash-partitioned table in 15.1 would be
> unrestorable in 15.2. They'd need to take a new pg_dump from 15.1 with
> "--load-via-partition-root" and then restore it in 15.2. Obviously that
> would be bad in any case, but it's more tolerable going between servers
> of different major versions.

Yeah.  Also, do we have this issue with hash indexes?  If so
reindexing might be necessary, which again would be more
palatable in a major release.

> So, given that this fix is unlikely to help many people in 15 and
> earlier, and that there's a chance that the fix is really painful for
> someone; I'm electing not to backpatch it.

+1

			regards, tom lane