How To Call SQL Server System Stored Procedures from RDO (166211)

SUMMARY

This article describes how to call system-stored procedures on SQL Server from RDO.

SQL Server has a number of prewritten, stored procedures that are used to configure and administer the SQL server. They are all located in the Master database and have the prefix [ASCII 147]sp_,[ASCII 148] which distinguishes them from user- or application-written stored procedures.

In order to call these stored procedures from RDO, you must specify the correct database in which they reside, the master database. There are several ways to do this, but the most effective way is to explicitly reference the stored procedure in your call syntax. For example:

   { ? = call master.dbo.sp_addlogin(?,?) }

Another method to accomplish this behavior is to set the default database before creating and executing your stored procedure. The following example uses a prepared statement and assumes that "Pubs" is your default database, cn is an active rdoConnection object, and qr is an rdoQuery object:

   cn .Execute "Use Master"
   qr.SQL  = "some sql to execute..."
   Set qr.ActiveConnection = cn
   qr .Execute
   cn .Execute "Use Pubs"

MORE INFORMATION

Start a new Standard EXE project. Form1 is created by default.
Add a CommandButton (Command1) to Form1.
From the Project menu, select References, and place a check next to Microsoft Remote Data Object 2.0.

Paste the following code into the General Declarations section of Form1:

      Private Sub Command1_Click()
         Dim cn As New rdoConnection
         Dim qr As New rdoquery

         With cn
         .Connect = "Driver={SQL Server};Server=MyServer;" & _
                  "Database=pubs;Uid=<username>;Pwd=<strong password>"
         .EstablishConnection Prompt = rdDriverNoPrompt
         End With

         With qr
            Set .ActiveConnection = cn
            'Note: If you don't specify master, you will get the following
            'error: "An invalid parameter was passed."
            .SQL = "{ ? = call master.dbo.sp_addlogin(?,?) }"
            .Prepared = True
            .BindThreshold = 1024 'largest column that will be bound under
                                  'ODBC.
            Debug.Print .rdoParameters.Count
            .rdoParameters(0).Direction = rdParamOutput
            .rdoParameters(1).Direction = rdParamInput
            .rdoParameters(2).Direction = rdParamInput
            .rdoParameters(1) = "Edward"
            .rdoParameters(2) = "Scissorhands"

            .Execute
            Debug.Print .rdoParameters(0).Value
            'Const SQL_SUCCESS As Long = 0
            'Const SQL_ERROR As Long = -1
         End With
      End Sub

Note that you need to change your DATABASE, UID, and PWD parameters in the Connect Property.
Start the program or press the F5 key.
Click the Command1 button to execute the stored procedure and display the parameter count and the output parameter in the debug window.

REFERENCES

In Visual Basic Books Online, please see:

  Guide to Building Client Server Applications in Visual Basic (Enterprise)
    Part 3: Data Access Options
      Using Remote Data Objects and the Remote Data Control
        Using RDO to Execute Stored Procedures