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Date: Fri, 11 Oct 2019 12:48:14 +0200
From: Christoph Berg <myon@debian.org>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
	Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Collation versioning
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Re: Thomas Munro 2019-10-11 <CA+hUKGKDe98DFWKJoS7e4Z+Oamzc-1sZfpL3V3PPgi1uNvQ1tw@mail.gmail.com>
> While testing pg_upgrade scenarios I noticed that initdb-created
> collations' versions are not preserved, potentially losing track of
> information about corrupted indexes.  That's a preexisting condition,
> and probably well understood, but it made me realise that if we switch
> to per-database object (for example: per index) version tracking as
> mentioned up-thread, then we should probably preserve that information
> across pg_upgrade.

That would make much sense, yes. The whole problem is already complex
enough, if we add another "but if you use pg_upgrade, you still need
to do the tracking manually" footnote, users will be very confused.

Christoph