Subject: Re: BUG #15285: Query used index over field with ICU collation in
 some cases wrongly return 0 rows
To: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>,
 Thomas Munro <thomas.munro@enterprisedb.com>
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Cc: Peter Geoghegan <pg@bowt.ie>,
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From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Organization: 2ndQuadrant
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Date: Wed, 2 Sep 2020 14:06:18 +0200
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On 2020-06-10 00:29, Jehan-Guillaume de Rorthais wrote:
> In the meantime, I've been working on various workarounds. The only one I found
> is to use "fr-u-kr-latn-digit-kn" instead of "fr-u-kr-latn-digit".
> Unfortunately, the two collations are not equivalent, but I believe it might be
> useful in many case.

What precisely is broken in the ICU library?  All the examples so far 
refer to kr-latn-digit.  Are all reorderings broken, or something 
specifically related to latn and/or digit?  Are any collation 
customizations other than reorderings affected?

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