From: Tom Lane <tgl@sss.pgh.pa.us>
To: Janne Annala <janne.annala@forenom.com>
cc: "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>
Subject: Re: NEW.* and OLD.* inside trigger function don't seem to contain
 recently added columns
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Comments: In-reply-to Janne Annala <janne.annala@forenom.com>
	message dated "Fri, 22 Mar 2024 16:59:37 -0000"
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Date: Fri, 22 Mar 2024 20:41:52 -0400
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Janne Annala <janne.annala@forenom.com> writes:
> Here's the minimum case to reproduce the issue:

> CREATE FUNCTION x()
>  RETURNS trigger
>  LANGUAGE plpgsql
> AS $function$
> BEGIN
>   IF ROW(NEW.*) IS DISTINCT FROM ROW(OLD.*) THEN

Try dropping the ROW() bit, that is just

   IF NEW.* IS DISTINCT FROM OLD.* THEN

or even

   IF NEW IS DISTINCT FROM OLD THEN

I think what is happening is that the ROW() notation is getting
expanded at parse time to

   ROW(NEW.id, NEW.old_column, NEW.updated)

and then there's no dependency on the original rowtype that would
lead to that expansion getting reconsidered.  Arguably that's a
bug, but it's not clear to me what the consequences of changing
that behavior would be.

			regards, tom lane