Re: BUG #14289: Potential bug: "invalid attribute number" when dblink result is assigned in PL/PGSQL

On 08/18/2016 01:44 PM, m(dot)overmeyer(at)yahoo(dot)ca wrote:
> The following bug has been logged on the website:
>
> Bug reference: 14289
> Logged by: Michael Overmeyer
> Email address: m(dot)overmeyer(at)yahoo(dot)ca
> PostgreSQL version: 9.5.4
> Operating system: CentOS 7, also Docker
> Description:
>
> I believe I may have found a bug in PL/PGSQL or dblink. When using the
> assignment operator to assign the results of dblink_build_sql_delete to a
> variable, it gives me:
>
> psql:pg_bug.sql:37: ERROR: 22023: invalid attribute number -1598
> CONTEXT: PL/pgSQL function test_assignment(int2vector) line 6 at
> assignment
> LOCATION: validate_pkattnums, dblink.c:2851

This does not have anything specific to do with dblink -- but it does
seem to be specific to plpgsql. Here is a minimal test case:

SELECT version();
version
--------------------------------------------------------------------
PostgreSQL 9.5.4 on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu
4.8.4-2ubuntu1~14.04.3) 4.8.4, 64-bit
(1 row)

CREATE OR REPLACE FUNCTION test_int2vector(pka int2vector)
RETURNS int2vector AS $$
BEGIN
return pka;
END;
$$ LANGUAGE plpgsql;

SELECT test_int2vector('1'::int2vector);
-- garbage result

CREATE OR REPLACE FUNCTION test_int2v(pka int2vector)
RETURNS int2vector AS
$$ select pka $$ LANGUAGE sql;

SELECT test_int2v('1'::int2vector);
-- works fine

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