Re: [WIP] UNNEST(REFCURSOR): allowing SELECT to consume data from a REFCURSOR

"Daniel Verite" <[email protected]> Tue, 14 Jan 2020 15:53:37 +0100
Newsgroups gmane.comp.db.postgresql.devel.general
Message-ID <[email protected]>
	Dent John wrote:

> It=E2=80=99s crashing when it=E2=80=99s checking that the returned tuple =
matches the
> declared return type in rsinfo->setDesc. Seems rsinfo->setDesc gets
> overwritten. So I think I have a memory management problem.

What is the expected result anyway? A single column with a "record"
type? FWIW I notice that with plpgsql, this is not allowed to happen:

CREATE FUNCTION cursor_unnest(x refcursor) returns setof record
as $$
declare
 r record;
begin
  loop
    fetch x into r;
    exit when not found;
    return next r;
  end loop;
end $$ language plpgsql;

begin;

declare c cursor for select oid::int as i, relname::text as r from pg_class;

select cursor_unnest('c');

ERROR:	set-valued function called in context that cannot accept a set
CONTEXT:  PL/pgSQL function cursor_unnest(refcursor) line 8 at RETURN NEXT


Best regards,
--=20
Daniel V=C3=A9rit=C3=A9
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