Subject: Re: Collation versioning
To: Julien Rouhaud <rjuju123@gmail.com>, Michael Paquier <michael@paquier.xyz>
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Cc: Thomas Munro <thomas.munro@gmail.com>, Robert Haas
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From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Organization: 2ndQuadrant
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Date: Tue, 15 Sep 2020 14:27:38 +0200
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On 2020-09-08 16:45, Julien Rouhaud wrote:
> I usually agree with that approach, I'm just afraid that getting a consensus on
> the best way to do that will induce a lot of discussions, while this is
> probably a corner case due to general usage of hash and bloom indexes.
> 
> Anyway, in order to make progress on that topic I attach an additional POC
> commit to add the required infrastructure to handle this case in
> v29-0001-Add-a-new-amnostablecollorder-flag-in-IndexAmRou.patch.

I'm confused now.  I think we had mostly agreed on the v28 patch set, 
without this additional AM flag.  There was still some discussion on 
what the AM flag's precise semantics should be.  Do we want to work that 
out first?

Btw., I'm uneasy about the term "stable collation order".  "Stable" has 
an established meaning for sorting.  It's really about whether the AM 
uses collations at all, right?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services