Execute oracle stored procedure from C# always returns null

Question

Hi,
I'm trying to execute a stored procedure on oracle 9i. I'm using .Net OracleClient provider.
Apparently, I can execute the stored procedure, but it always returns null as a result (actually all the sp's I have there returns null)! I can execute any text statement against the database successfully, and also I can execute the stored procedure using Toad.
This is not the first time for me to call an oracle stored procedure, but this really is giving me a hard time! Can anyone help please?
Below are the SP, and the code used from .Net to call it, if that can help.
Oracle SP:
CREATE OR REPLACE PROCEDURE APIECARE.CHECK_EXISTENCE(l_number IN NUMBER) AS
v_status VARCHAR2(5) := NULL;
BEGIN
BEGIN
SELECT CHECK_NO_EXISTENCE(to_char(l_number))
INTO v_status
FROM DUAL;
EXCEPTION WHEN OTHERS THEN
v_status := NULL;
END;
DBMS_OUTPUT.PUT_LINE(v_status);
END CHECK_CONTRNO_EXISTENCE;
C# Code:
string connStr = "Data Source=datasource;Persist Security Info=True;User ID=user;Password=pass;Unicode=True";
OracleConnection conn = new OracleConnection(connStr);
OracleParameter param1 = new OracleParameter();
param1.ParameterName = "v_status";
param1.OracleType = OracleType.VarChar;
param1.Size = 5;
param1.Direction = ParameterDirection.Input;
OracleParameter param2 = new OracleParameter();
param2.ParameterName = "l_number";
param2.OracleType = OracleType.Number;
param2.Direction = ParameterDirection.Input;
param2.Value = 006550249;
OracleParameter[] oraParams = new OracleParameter[] { param1, param2 };
OracleCommand cmd = new OracleCommand("CHECK_EXISTENCE", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(oraParams);
conn.Open();
object result = cmd.ExecuteScalar();
conn.Close();

Answer 1

Hi,
Does that actually execute? You're passing two parameters to a procedure that only takews 1 and get no error?
Your stored procedure doesnt return anything and has no output parameters, what are you expecting to be returned exactly?
If you're trying to access V_STATUS you'll need to declare that as either an output parameter of the procedure, or return value of the function, and also access it via accessing Param.Value, not as the result of ExecuteScalar.
See if this helps.
Cheers,
Greg
create or replace function myfunc(myinvar in varchar2, myoutvar out varchar2) return varchar2
is
retval varchar2(50);
begin
myoutvar := myinvar;
retval := 'the return value';
return retval;
end;
using System;
using System.Data;
using Oracle.DataAccess.Client;
public class odpfuncparams
     public static void Main()
      OracleConnection con = new OracleConnection("user id=scott;password=tiger;data source=orcl");
      con.Open();
      OracleCommand cmd = new OracleCommand("myfunc", con);
      cmd.CommandType = CommandType.StoredProcedure;
      OracleParameter retval = new OracleParameter("retval",OracleDbType.Varchar2,50);
      retval.Direction = ParameterDirection.ReturnValue;
      cmd.Parameters.Add(retval);
      OracleParameter inval = new OracleParameter("inval",OracleDbType.Varchar2);
      inval.Direction = ParameterDirection.Input; 
      inval.Value="hello world";
      cmd.Parameters.Add(inval);
      OracleParameter outval = new OracleParameter("outval",OracleDbType.Varchar2,50);
      outval.Direction = ParameterDirection.Output;
      cmd.Parameters.Add(outval);
      cmd.ExecuteNonQuery();
      Console.WriteLine("return value is {0}, out value is {1}",retval.Value,outval.Value);
      con.Close();
}