Re: PostgreSQL Bug with simple function unexpectedly treating varchar parameter as an array

No ... just one version:

xxxx_pub_dev_2_db=# SHOW server_version;
server_version
----------------
16.9
(1 row)

xxxx_pub_dev_2_db=# DROP FUNCTION if exists _sa_setup_role;
DROP FUNCTION
xxxx_pub_dev_2_db=# CREATE OR REPLACE FUNCTION _sa_setup_role(
p_role_to_be_granted varchar)
xxxx_pub_dev_2_db-# RETURNS varchar
xxxx_pub_dev_2_db-# LANGUAGE plpgsql
xxxx_pub_dev_2_db-# AS
xxxx_pub_dev_2_db-# $function$
xxxx_pub_dev_2_db$# declare
xxxx_pub_dev_2_db$# begin
xxxx_pub_dev_2_db$# raise info '%',p_role_to_be_granted::varchar;
xxxx_pub_dev_2_db$# return('Done');
xxxx_pub_dev_2_db$# end;
xxxx_pub_dev_2_db$# $function$;
CREATE FUNCTION
xxxx_pub_dev_2_db=# select _sa_setup_role('af_repo_app');
ERROR: malformed array literal: "af_repo_app"
LINE 1: select _sa_setup_role('af_repo_app');
^
DETAIL: Array value must start with "{" or dimension information.
xxxx_pub_dev_2_db=# select _sa_setup_role('af_repo_app'::varchar);
INFO: af_repo_app
_sa_setup_role
----------------
Done
(1 row)

xxxx_pub_dev_2_db=# \df _sa_setup_role
List of functions
Schema | Name | Result data type | Argument data types
| Type
--------+----------------+-------------------+----------------------------------------+------
sqlapp | _sa_setup_role | character varying | p_role_to_be_granted
character varying | func
(1 row)

On Fri, Jul 25, 2025 at 12:54 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Rumpi Gravenstein <rgravens(at)gmail(dot)com> writes:
> > I've been confound by the following behavior that I see in one of our
> > PostgreSQL 16 instances. In this case I am running this script from
> psql.
>
> I'd bet there is another function named _sa_setup_role() that takes
> some kind of array, and the parser is resolving the ambiguity by
> choosing that one.
>
> "\df _sa_setup_role" would be illuminating.
>
> regards, tom lane
>

--
Rumpi Gravenstein