How To Call System-Stored Procedures on SQL Server from RDO

• Enterprise Edition of Microsoft Visual Basic, 32-bit only, for Windows, version 4.0

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. All of these procedures have the prefix "sp_" that distinguishes them from user- or application-written stored procedures.

In order to call these stored procedures from RDO, you must specify the correct database is 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(?,?) }

   <Object>.Execute "Use Master"  'rdoConnection object
   Set <Object> = <Object>.CreatePreparedStatement("", strSQL)
   <Object>.Execute               'rdoPreparedStatement object
   <Object>.Execute "Use Pubs"    'rdoConnection object

MORE INFORMATION

1. Start a new project in Visual Basic. Form1 is created by default.

2. Add a Command button, Command1, to Form1.

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

      Private Sub Command1_Click()
        Dim en As rdoEnvironment
        Dim cn As rdoConnection
        Dim rs As rdoResultset
   
        Dim strConnect As String
        Dim strSQL As String
   
        Set en = rdoEnvironments(0)
        en.CursorDriver = rdUseOdbc
   
        strConnect = "Driver={SQL Server}; Server=MyServer; " & _
          "Database=pubs; Uid=sa; Pwd="
        Set cn = en.OpenConnection(dsName:="", Prompt:=rdDriverNoPrompt, _
          ReadOnly:=False, Connect:=strConnect)
   
        Dim ps As rdoPreparedStatement
   
        'Note: If you don't specify master, you will get this following error:
        '"An invalid parameter was passed."
   
        strSQL = "{ ? = call master.dbo.sp_addlogin(?,?) }"
        Set ps = cn.CreatePreparedStatement("", strSQL)
        ps.BindThreshold = 1024 'largest column that will be bound under ODBC.
        Debug.Print ps.rdoParameters.Count
        ps.rdoParameters(0).Direction = rdParamOutput
        ps.rdoParameters(1).Direction = rdParamInput
        ps.rdoParameters(2).Direction = rdParamInput
   
        \* Note to KB editor: don't change this to "John Doe"
        ps.rdoParameters(1) = "Edward"
        ps.rdoParameters(2) = "Scissorhands"
   
        ps.Execute
        Debug.Print ps.rdoParameters(0).Value
      End Sub
   
   

4. Note that you need to change your DATABASE, UID, and PWD parameters in the OpenConnection method.

5. Start the program or press the F5 key.

6. Click the Command1 button to execute the stored procedure and display the parameter count and the output parameter in the debug window.

REFERENCES

Hitchhiker's Guide to Visual Basic and SQL Server, Microsoft Press. ISBN: 1-55615-906-4.