From: Tom Lane <tgl@sss.pgh.pa.us>
To: chu_z@hotmail.com
cc: pgsql-docs@lists.postgresql.org
Subject: Re: Correction
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 <165844944334.271448.18067658391804504480@wrigleys.postgresql.org>
References: <165844944334.271448.18067658391804504480@wrigleys.postgresql.org>
Comments: In-reply-to PG Doc comments form <noreply@postgresql.org>
	message dated "Fri, 22 Jul 2022 00:24:03 -0000"
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Date: Sun, 24 Jul 2022 15:39:17 -0400
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PG Doc comments form <noreply@postgresql.org> writes:
> "If you declare a column as UNIQUE or PRIMARY KEY, the implicitly generated
> index is case-sensitive. So it's useless for case-insensitive searches, and
> it won't enforce uniqueness case-insensitively."

> I think the statement above is not correct. I tried creating a PK or unique
> key index on a CITEXT column. It checks uniqueness in case-insensitivity.

That paragraph is talking about what happens when you *don't* use citext.

			regards, tom lane