From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
To: Daniel Verite <daniel@manitou-mail.org>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: insensitive collations
Date: Thu, 10 Jan 2019 08:49:48 +0100
Message-ID: <91759904-5093-de4c-1e54-e1eb18174210@2ndquadrant.com> (raw)
In-Reply-To: <bf0e38ff-691d-404f-a7a0-b88b22300cb8@manitou-mail.org>
References: <bf0e38ff-691d-404f-a7a0-b88b22300cb8@manitou-mail.org>
On 09/01/2019 22:01, Daniel Verite wrote:
>> I don't see anything wrong here. The collation says that both values
>> are equal, so which one is returned is implementation-dependent.
> Is it, but it's impractical if the product of seemingly the same GROUP BY
> flip-flops between its different valid results. If it can't be avoided, then
> okay. If it can be avoided at little cost, then it would be better to do it.
But there is no concept of which one of these is the preferred variant,
so I don't see how the system is supposed to pick one and then stick to
it across separate query invocations.
--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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To: pgsql-hackers@postgresql.org
Cc: peter.eisentraut@2ndquadrant.com, daniel@manitou-mail.org
Subject: Re: insensitive collations
In-Reply-To: <91759904-5093-de4c-1e54-e1eb18174210@2ndquadrant.com>
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