HOWTO: Pass a Date Value to a Oracle Stored Procedure

• Microsoft Visual Basic Enterprise Edition for Windows, version 5.0

SUMMARY

This article gives an example of passing a Date datatype value to an Oracle stored procedure and getting back a result from the stored procedure. The example below uses RDO 2.0, and the second version, 2.73.7253, of the Microsoft Oracle ODBC driver. Note that the first version of the Microsoft Oracle ODBC driver, Ver 2.00.006325, does not support passing dates to a stored procedure.

This example also demonstrates how the ODBC will take care of converting the Visual Basic Date to the acceptable Oracle Date format.

MORE INFORMATION

Create a new project in Visual Basic and reference the Microsoft Remote Data Object 2.0 under Project/References.

1. On the new Form add a CommandButton.

2. Paste the following code in the General Declarations section of the Form:

   Option Explicit Dim Cn As New rdoConnection Dim En As rdoEnvironment Dim Qd As New rdoQuery Dim Rs As rdoResultset Dim Conn As String Dim tempcnt As Integer

      Private Sub Command1_Click()
   
          Dim strDate, strQd$, strQd1$
          strDate = InputBox("Enter the date you wish to retrieve:")
          Qd(0) = CDate(strDate)
          Qd.Execute
          strQd = Mid(Qd(1), 12)
          strQd1 = Mid(Qd(1), 1, 11)
          Debug.Print "For the date you entered: " & strQd1 & vbCrLf & strQd
          MsgBox "For the date you entered: " & strQd1 & vbCrLf & strQd
   
      End Sub
   
      Private Sub Form_Load()
   
          Command1.Caption = "Start"
          'Change each <> field to the appropriate value for your system
          Conn = "UID=<uid>;PWD=<password>;" _
          & "driver={Microsoft ODBC for Oracle};SERVER=<server>;"
   
          Set En = rdoEnvironments(0)
          En.CursorDriver = rdUseOdbc
          With Cn
              .Connect = Conn
              .CursorDriver = rdUseOdbc
              .EstablishConnection rdDriverNoPrompt, False
          End With
   
          Set Qd.ActiveConnection = Cn
   
          Qd.SQL = "{call testdate1(?,?)}"
          Qd(0).Direction = rdParamInput
          Qd(1).Direction = rdParamOutput
          Qd(0).Type = rdTypeDATE
   
      End Sub
   
      Private Sub Form_Unload(Cancel As Integer)
          Qd.Close
          Cn.Close
          En.Close
   
      End Sub
   
   

3. Create an Oracle stored procedure using this script:

   CREATE OR REPLACE PROCEDURE TESTDATE1(

      /* This is called by a Visual Basic project that passes in */
      /* a Date parameter in any Visual Basic-acceptable format and */
      /* returns a Count value and the input date in */
      /* a different format */
   
         INDATE IN DATE,
         OUTSTR OUT VARCHAR2 )
   
      IS
   
         m_Count NUMBER;
   
      BEGIN
         SELECT
         COUNT(*) INTO m_Count
         FROM EMP WHERE HIREDATE < INDATE;
   
         OUTSTR:=TO_CHAR(INDATE,'DD-Mon-YYYY') ||
         'The Count is: '|| TO_CHAR(m_Count);
   
      END;
      /
   
   

Additional Information:

1. This stored procedure uses the DEMO account EMP table supplied in a standard Oracle 7.3 installation.

2. This demonstrates that the Microsoft Oracle ODBC driver will handle Date conversion from an acceptable Visual Basic format to an acceptable Oracle format.

REFERENCES

For additional information, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q167225
   TITLE     : HOWTO: Access an Oracle Database Using RDO

Keywords          : vb5all vb5howto
Technology        : kbodbc
Version           : WINDOWS:5.0
Platform          : WINDOWS
Hardware          : x86
Issue type        : kbhowto