Thread: How to callproc a PL/pgSQL function a cursor OUT parameter and two OUT parameters

On 10/04/2014 09:16 AM, Néstor Boscán wrote:
> Hi
>
> I have a PL/pgSQL that looks like this:
>
> create or replace function my_function (p_cursor out refcursor, p_code
> out varchar, p_message out varchar) as $$
>   begin
>     open p_cursor for
>       select * from table;
>     p_code := 'AJ001';
>
>     return;
>   end; $$ language plpgsql;
>
> I've tried to invoke this function using:
>
> cursor.callproc('schema.my_function', [ 'mycursor', code, message ])
>
> But I get:
>
> HINT:  Ninguna funci├│n coincide en el nombre y tipos de argumentos.
> Puede ser necesario agregar conversión explícita de tipos.
>
> In english is something like No function matches the name and types of
> arguments.
>
> Any ideas?

http://www.postgresql.org/docs/9.3/interactive/xfunc-sql.html#XFUNC-OUTPUT-PARAMETERS

"Notice that output parameters are not included in the calling argument
list when invoking such a function from SQL. This is because PostgreSQL
considers only the input parameters to define the function's calling
signature. That means also that only the input parameters matter when
referencing the function for purposes such as dropping it. We could drop
the above function with either of.."


So drop the OUT variables from your function call.

>
> Regards,
>
> Néstor


--
Adrian Klaver
adrian.klaver@aklaver.com

On 10/04/2014 10:18 AM, Néstor Boscán wrote:

CCing list.
> So in PL/pgSQL I can't have a function with a cursor and out parameters?

I don't know I have not tried. Whether it works or not is not related to
the error message you are getting. OUT parameters are for output only,
they are declared in the function creation but not used when calling the
function. The fact that you are passing them in as arguments(including
the refcursor name) when calling the function is what is causing the
error. The way you are calling the function makes Postgres look for a
function with the signature of something like:

my_function(text, text, text)

when in reality your function has the signature of:

my_function()

There is no version of my_function that has the first signature so you
get the error.

The section I linked to has examples showing how to work with OUT
parameters. The examples use SQL functions, but the same thing applies
to plpgsl functions.


>
> Regards,
>
> Néstor
>
> On Sat, Oct 4, 2014 at 12:21 PM, Adrian Klaver
> <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>> wrote:
>
>     On 10/04/2014 09:16 AM, Néstor Boscán wrote:
>
>         Hi
>
>         I have a PL/pgSQL that looks like this:
>
>         create or replace function my_function (p_cursor out refcursor,
>         p_code out varchar, p_message out varchar) as $$
>            begin
>              open p_cursor for
>                select * from table;
>              p_code := 'AJ001';
>
>              return;
>            end; $$ language plpgsql;
>
>         I've tried to invoke this function using:
>
>         cursor.callproc('schema.my___function', [ 'mycursor', code,
>         message ])
>
>         But I get:
>
>         HINT:  Ninguna funci├│n coincide en el nombre y tipos de
>         argumentos. Puede ser necesario agregar conversión explícita
>         de tipos.
>
>         In english is something like No function matches the name and
>         types of arguments.
>
>         Any ideas?
>
>
>     http://www.postgresql.org/__docs/9.3/interactive/xfunc-__sql.html#XFUNC-OUTPUT-__PARAMETERS
>     <http://www.postgresql.org/docs/9.3/interactive/xfunc-sql.html#XFUNC-OUTPUT-PARAMETERS>
>
>     "Notice that output parameters are not included in the calling
>     argument list when invoking such a function from SQL. This is
>     because PostgreSQL considers only the input parameters to define the
>     function's calling signature. That means also that only the input
>     parameters matter when referencing the function for purposes such as
>     dropping it. We could drop the above function with either of.."
>
>
>     So drop the OUT variables from your function call.
>
>
>         Regards,
>
>         Néstor
>
>
>
>     --
>     Adrian Klaver
>     adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
>
>


--
Adrian Klaver
adrian.klaver@aklaver.com