Date: Wed, 24 Dec 2025 14:47:01 -0500
From: Bruce Momjian <bruce@momjian.us>
To: Bernice Southey <bernice.southey@gmail.com>
Cc: pgsql-docs@lists.postgresql.org
Subject: Re: More guidance on ctid
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On Wed, Dec 24, 2025 at 07:38:07PM +0000, Bernice Southey wrote:
> Bruce Momjian <bruce@momjian.us> wrote:
> > We could go in the direction you suggested, but it seems out-of-place in
> > the UPDATE/DELETE docs since it gets into a lot of details.  Maybe in
> > the locking chapter?
> How about if the UPDATE and DELETE examples only show how to get limit
> and order by with a cte, and remove all references to locking. No for
> update, deadlocks etc. The examples use primary keys and not ctid.
> Anyone just trying to do simple limit and order by without locking
> problems will get what they need, and won't be confused by the locking
> complexity. Anyone trying to solve lock contention needs to understand
> locking and should be looking at that chapter. The explanation for
> deadlock avoidance should be there as you suggest. Perhaps the update
> and delete examples can link to them. If you think this is the right
> approach I'm willing to give it a go?

I am not the author of the original ctid doc patch, but I believe the
goal was to use ctid so we don't need to use needless index lookups for
primary keys.

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

  Do not let urgent matters crowd out time for investment in the future.