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Message-ID: <b0ff0233-b9e2-48ef-ac27-f69bca73f8f4@eisentraut.org>
Date: Thu, 2 May 2024 15:38:32 +0200
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Subject: Re: Support LIKE with nondeterministic collations
To: Daniel Verite <daniel@manitou-mail.org>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
References: <a827cf68-608e-45cf-9b94-e46f5e9d4171@manitou-mail.org>
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From: Peter Eisentraut <peter@eisentraut.org>
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On 30.04.24 14:39, Daniel Verite wrote:
>    postgres=# SELECT '.foo.' like '_oo' COLLATE ign_punct;
>     ?column?
>    ----------
>     f
>    (1 row)
> 
> The first two results look fine, but the next one is inconsistent.

This is correct, because '_' means "any single character".  This is 
independent of the collation.

I think with nondeterministic collations, the single-character wildcard 
is often not going to be all that useful.