From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Ray O'Donnell" <ray@rodonnell.ie>
cc: "'PostgreSQL'" <pgsql-general@postgresql.org>
Subject: Re: Combining scalar and row types in RETURNING
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Comments: In-reply-to "Ray O'Donnell" <ray@rodonnell.ie>
	message dated "Tue, 03 Jun 2025 18:18:51 -0000"
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Date: Tue, 03 Jun 2025 15:31:34 -0400
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"Ray O'Donnell" <ray@rodonnell.ie> writes:
> (iii) Running (ii) but with the order of the items in RETURNING reversed -
>      ... returning t, merge_action() into m_new, m_action
> - gave me a different error:
> ERROR:  record variable cannot be part of multiple-item INTO list
> LINE 53:         m, merge_action() into m_new, m_action
> ...which seems to answer my question definitively.

Ah, after looking at the source code in that area, plpgsql
allows the INTO target to be either a single composite
variable, or one or more non-composite variables; the
argument being that otherwise it's too hard to decide which
RETURNING items match which INTO items.

But I think maybe there is still a solution:

declare
     m_into record;
...
     returning
         merge_action() m, t
     into
         m_into;

... then fetch m_into.m and m_into.t (the latter will be
a composite field).  I didn't try this approach though.

			regards, tom lane