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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Yugo NAGATA <nagata@sraoss.co.jp>
cc: "David G. Johnston" <david.g.johnston@gmail.com>,
        Peter Eisentraut <peter@eisentraut.org>,
        David Rowley <dgrowleyml@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Document NULL
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Comments: In-reply-to Yugo NAGATA <nagata@sraoss.co.jp>
	message dated "Wed, 19 Jun 2024 14:15:20 +0900"
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Date: Wed, 19 Jun 2024 01:45:43 -0400
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Yugo NAGATA <nagata@sraoss.co.jp> writes:
> On Tue, 18 Jun 2024 20:56:58 -0700
> "David G. Johnston" <david.g.johnston@gmail.com> wrote:
>> But it is neither a keyword nor an identifier.

The lexer would be quite surprised by your claim that NULL isn't
a keyword.  Per src/include/parser/kwlist.h, NULL is a keyword,
and a fully reserved one at that.

			regards, tom lane