On Tue, 11 Nov 2025 at 05:52, PG Doc comments form
<noreply@postgresql.org> wrote:
> "Variable substitution currently works only in SELECT, INSERT, UPDATE,
> DELETE, and commands containing one of these..."
> https://www.postgresql.org/docs/current/plpgsql-implementation.html#PLPGSQL-VAR-SUBST
> But experiments showed that variable substitution works for MERGE command
> too.
Thanks for the report. You're right that this has been overlooked.
The attached patch fixes it. I can take care of this once the back
branches are open again after the minor releases are out.
David