From: Tom Lane <tgl@sss.pgh.pa.us>
To: y.saburov@gmail.com
cc: pgsql-docs@lists.postgresql.org
Subject: Re: The examples given in Chapter 14 are not true.
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	message dated "Sun, 26 May 2024 13:58:17 -0000"
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Date: Sun, 26 May 2024 10:35:34 -0400
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PG Doc comments form <noreply@postgresql.org> writes:
> Page: https://www.postgresql.org/docs/16/performance-tips.html

> 1) How did you create the `tenk1` table?

As the text says, it's supposed to be made by running the core
regression tests ("make installcheck").

> 1) relpages for table `tenk1` - different in version 16. Some calculations
> will be incorrect accordingly
> 2) you will not be able to reproduce examples for which there are no indexes
> in table `tenk1` - for example index `index_tenk1_on_four`.

Yeah, that's a bit out of date.  I fixed it up awhile ago for v17:

https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=5caa05749

However, the text also points out that you won't necessarily get
exactly the same results as are shown, for assorted reasons of
which different-version is only one.  So I think these changes
were more neatnik-ism than rescuing the chapter from total
irrelevancy.

			regards, tom lane