Date: Wed, 22 Dec 2021 17:13:17 -0500
From: Bruce Momjian <bruce@momjian.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
Cc: Chris Lowder <clowder@hey.com>,
	Pg Docs <pgsql-docs@lists.postgresql.org>
Subject: Re: 11.7. Indexes on Expressions
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On Wed, Dec 22, 2021 at 05:09:53PM -0500, Bruce Momjian wrote:
> On Wed, Dec 22, 2021 at 03:06:12PM -0700, David G. Johnston wrote:
> > On Wed, Dec 22, 2021 at 2:45 PM Bruce Momjian <bruce@momjian.us> wrote:
> >     Not sure what else we can do --- it would be odd to explain it in the
> >     expression index docs.
> > 
> > 
> > 
> > Found another one:
> > 
> > https://www.postgresql.org/docs/current/btree-implementation.html
> > "...(where most individual updates cannot apply the HOT optimization."
> > 
> > Make the acronym HOT in all these places take the reader to the acronym page,
> > and add a brief description there so they don't need to consume the readme
> > file?
> 
> Wow, I don't think the acronym page is the right place for this --- I
> think we need a new section for this somewhere.

I think our _big_ missing information is a definition of HOT updates and
that updating a column involved in an index disables HOT updates.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  If only the physical world exists, free will is an illusion.