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-docs-owner+archive@lists.postgresql.org>)
	id 1taIDq-000VJk-2Y
	for pgsql-docs@arkaria.postgresql.org; Tue, 21 Jan 2025 17:39:30 +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-docs-owner+archive@lists.postgresql.org>)
	id 1taIDp-002Zkr-5T
	for pgsql-docs@arkaria.postgresql.org; Tue, 21 Jan 2025 17:39:29 +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 <tgl@sss.pgh.pa.us>)
	id 1taIDo-002Zki-Up
	for pgsql-docs@lists.postgresql.org; Tue, 21 Jan 2025 17:39:28 +0000
Received: from sss.pgh.pa.us ([68.162.161.243])
	by makus.postgresql.org with esmtps  (TLS1.3) tls
 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.96)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1taIDm-000laF-2Z
	for pgsql-docs@lists.postgresql.org;
	Tue, 21 Jan 2025 17:39:28 +0000
Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1])
	by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 50LHdPng3359765;
	Tue, 21 Jan 2025 12:39:25 -0500
From: Tom Lane <tgl@sss.pgh.pa.us>
To: oselemg@gmail.com
cc: pgsql-docs@lists.postgresql.org
Subject: Re: Typo on tutorial window page
In-reply-to: <173737973383.1070.1832752929070067441@wrigleys.postgresql.org>
References: <173737973383.1070.1832752929070067441@wrigleys.postgresql.org>
Comments: In-reply-to PG Doc comments form <noreply@postgresql.org>
	message dated "Mon, 20 Jan 2025 13:28:53 +0000"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <3359763.1737481165.1@sss.pgh.pa.us>
Date: Tue, 21 Jan 2025 12:39:25 -0500
Message-ID: <3359764.1737481165@sss.pgh.pa.us>
List-Id: <pgsql-docs.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-docs@lists.postgresql.org>
List-Owner: <mailto:pgsql-docs-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-docs>
Archived-At: 
 <https://www.postgresql.org/message-id/3359764.1737481165%40sss.pgh.pa.us>
Precedence: bulk

PG Doc comments form <noreply@postgresql.org> writes:
> EXPECTED:
> As shown here, the rank function produces a numerical rank for each distinct
> PARTITION BY value in the current row's partition, using the order defined
> by the ORDER BY clause. rank needs no explicit parameter, because its
> behavior is entirely determined by the OVER clause.

> ACTUAL:
> As shown here, the rank function produces a numerical rank for each distinct
> ORDER BY value in the current row's partition, using the order defined by
> the ORDER BY clause. rank needs no explicit parameter, because its behavior
> is entirely determined by the OVER clause.

Hmm, I think the current text is correct, or at least more nearly
correct than what you suggest.  Look at the example:

<programlisting>
SELECT depname, empno, salary,
       rank() OVER (PARTITION BY depname ORDER BY salary DESC)
FROM empsalary;
</programlisting>

<screen>
  depname  | empno | salary | rank
-----------+-------+--------+------
 develop   |     8 |   6000 |    1
 develop   |    10 |   5200 |    2
 develop   |    11 |   5200 |    2
 develop   |     9 |   4500 |    4
 develop   |     7 |   4200 |    5
 personnel |     2 |   3900 |    1
 personnel |     5 |   3500 |    2
 sales     |     1 |   5000 |    1
 sales     |     4 |   4800 |    2
 sales     |     3 |   4800 |    2
(10 rows)
</screen>

The ranks are separate within each partition (depname), and
within a partition rows having the same salary get the
same rank.

			regards, tom lane