Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps  (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.94.2)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1t0JkZ-00AjQV-6k
	for pgsql-hackers@arkaria.postgresql.org; Mon, 14 Oct 2024 12:00:35 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.94.2)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1t0JkW-00D90h-Qb
	for pgsql-hackers@arkaria.postgresql.org; Mon, 14 Oct 2024 12:00:33 +0000
Received: from makus.postgresql.org ([2001:4800:3e1:1::229])
	by malur.postgresql.org with esmtps  (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.94.2)
	(envelope-from <d.garsh@arenadata.io>)
	id 1t0JkW-00D90Z-DK
	for pgsql-hackers@lists.postgresql.org; Mon, 14 Oct 2024 12:00:32 +0000
Received: from forward502a.mail.yandex.net ([178.154.239.82])
	by makus.postgresql.org with esmtps  (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.94.2)
	(envelope-from <d.garsh@arenadata.io>)
	id 1t0JkR-000pXP-Ua
	for pgsql-hackers@lists.postgresql.org; Mon, 14 Oct 2024 12:00:31 +0000
Received: from mail-nwsmtp-smtp-production-main-51.vla.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-51.vla.yp-c.yandex.net [IPv6:2a02:6b8:c0f:4c80:0:640:a0f:0])
	by forward502a.mail.yandex.net (Yandex) with ESMTPS id EECF861275
	for <pgsql-hackers@lists.postgresql.org>; Mon, 14 Oct 2024 15:00:23 +0300 (MSK)
Received: by mail-nwsmtp-smtp-production-main-51.vla.yp-c.yandex.net (smtp/Yandex) with ESMTPSA id M0J1JmHIZ0U0-g6Zdbqkq;
	Mon, 14 Oct 2024 15:00:23 +0300
X-Yandex-Fwd: 1
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arenadata.io;
	s=mail; t=1728907223;
	bh=AdiBozrseK9N1xOarBC6v7oNQaJ9j8IW6kxiuwLPDCU=;
	h=In-Reply-To:From:Date:References:To:Subject:Message-ID;
	b=jyzKdOOBCxl5ERW9lQ34yFogMXpFnMMEk+SRUTzEzj0fOQoEzyYtxTpf4GlJ/tLze
	 C7QvpB8OmVhIp4GF7P7Ybl5HYXMMLmTQgHiw82JNqHNWFy3gxg2NxS8BmQkom+t1CE
	 XL1lUkwVIvX8bh3CcFI5W0iX3TuKn7k+LvGamPas=
Authentication-Results: mail-nwsmtp-smtp-production-main-51.vla.yp-c.yandex.net; dkim=pass header.i=@arenadata.io
Message-ID: <1356f2c2-d958-4177-b34b-a9f29ff1e125@arenadata.io>
Date: Mon, 14 Oct 2024 15:00:21 +0300
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: Add system column support to the USING clause
To: "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
References: <333431726204057@mail.yandex.ru> <86136.1726239379@sss.pgh.pa.us>
Content-Language: en-US
From: Denis Garsh <d.garsh@arenadata.io>
In-Reply-To: <86136.1726239379@sss.pgh.pa.us>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
X-Yandex-Filter: 1
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Archived-At: <https://www.postgresql.org/message-id/1356f2c2-d958-4177-b34b-a9f29ff1e125%40arenadata.io>
Precedence: bulk

If we are not going to implement this functionality, maybe it’s worth 
adding an explicit description to the 
[documentation](https://www.postgresql.org/docs/current/queries-table-expressions.html)? 
A note like: "JOIN USING doesn’t support system columns. If you need to 
join tables by a system column, use the JOIN ON clause."

-- 
Best regards,
Denis Garsh,
C Developer,
d.garsh@arenadata.io