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Message-ID: <0f5ad1359ca05bb3e77c346aa012b1df1d8f5429.camel@cybertec.at>
Subject: Re: Difference between C and en_US.UTF-8 Collate & CType in
 Postgres 10.x
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Debraj Manna <subharaj.manna@gmail.com>, pgsql-admin
	 <pgsql-admin@postgresql.org>
Date: Fri, 14 Sep 2018 13:57:38 +0200
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Debraj Manna wrote:
> Can someone let me know what is the difference we are expected to observe if we set
> Collate & Ctype to C as against  en_US.UTF-8 with encoding set to UTF8 in both the cases ?

For one, the ordering will be substantially different.

Compare the result of these two queries:

SELECT chr(i) FROM generate_series(1, 50000) i ORDER BY chr(i) COLLATE "C";
SELECT chr(i) FROM generate_series(1, 50000) i ORDER BY chr(i) COLLATE "en_US.utf8";

Yours,
Laurenz Albe