External Procedures

[silvia23]

Hello,
I need to use an external dll with a method in C. In order to do that, I've done the following steps:

1.- Generate the DLL with the export function inside:
__declspec(dllexport) int __cdecl CFunc(int seed)
{
...
}


2.- Create a PL/SQL Library

CREATE OR REPLACE LIBRARY mylib IS
'C:\ORANT\PLSQL80\MyDLL.dll';


3.- Create a script to call external functions:

CREATE or REPLACE FUNCTION rand (
seed INTEGER)
RETURN INTEGER AS EXTERNAL
LIBRARY mylib
NAME "CFunct"
LANGUAGE C;
/

CREATE or REPLACE PROCEDURE run_demo IS
al INTEGER;
BEGIN
begin
al := rand(100);
...
exception when others
then
dbms_output.put_line('SQL Error: ' || sqlerrm);
end;
end;
/

But when I call the procedure an error occur:
SQL> execute run_demo;
SQL Error: ORA-28575: no se ha podido abrir la conexión RPC con el agente de procedimiento externo

If necessary change something to file tnsnames.ora?¿
Thanks a lot,
Silvia

 

[JamesCrawford]

Hi Silvia

I had the same problem a while back and I added an extproc_connection_data parameter to my tnsnames file, this seemed to clear up the problem for me. There is lots of info on this error on metalink.

HTH

James

 

[silvia23]

Thanks a lot!!!
The initial problem was solved configuring the files tnsnames.ora and listener.ora, but a new problem has appeared:

SQL> exec run_demo;
SQL Error: ORA-06521: PL/SQL: Error al crear la correspondencia de la función
ORA-06522: Unable to
load symbol from DLL

Procedimiento PL/SQL terminado con éxito.

What mechanism is used by Oracle to map the functions?¿ Because when I try to call an internal function belonged to an Oracle package the same error appear.
Any idea?¿
Thanks again,
Silvia