HOWTO: Use RDS from Inside a Visual Basic Program (165297)

MORE INFORMATION

Sample Program

This example uses the CreateObject method of the RDS.DataSpace on the client to create a new instance of the RDSServer.DataFactory object on a remote server over HTTP. The RDSServer.DataFactory object then uses the Query method to execute SQL on the remote server and return an ADO/R recordset to the client.

In order to run the example code you first need to make sure the RDS Server components have been installed on the Internet Information Server (IIS) computer. You can download these from the Microsoft Universal Data Access web page located at the following Microsoft Web site: The client components must also be installed on the client computers. If the client computer has Internet Explorer 4.01 or later installed, the RDS 1.5 (or later) client components are included. For clients running Internet Explorer 3.0, the client components must be downloaded to the clients computer. One way of doing this is by using a CODEBASE parameter in the OBJECT tag of an HTML page. To do this go to the sample page on your RDS Server located at: The components will automatically be installed on the client.

Before you run this code, first make change the security settings. For additional information about configuration of RDS on the server side, click the following article number to view the article in the Microsoft Knowledge Base: This sample uses SQL Server and the Pubs database, but you can change the System DSN, UID, PWD, and SQL to match any ODBC database that you use.

Note You must change Username=<username> and PWD=<strong password> to the correct values before you run this code. Make sure that Username has the appropriate permissions to perform this operation on the database.

1. Start a new project in Visual Basic and choose "Standard EXE." Form1 is created by default.
2. Add two Command buttons, named Command1 and Command2, to Form1.
3. Paste the following code into the General Declarations section of Form1:

      Dim rs As Object   'Recordset
      Dim ds As Object   'RDS.DataSpace
      Dim df As Object   'RDSServer.DataFactory
   
      Private Sub Form_Load()
      Set ds = CreateObject("RDS.DataSpace")
      Set df = ds.CreateObject("RDSServer.DataFactory", _
      "http://myserver")
      End Sub
   
      Private Sub Command1_Click()
      'This query returns a recordset over HTTP.
      Dim strCn As Variant, strSQL As Variant
      strCn = "dsn=pubs;Username=<username>;PWD=<strong password>"
      strSQL = "select * from authors"
      Set rs = df.Query(strCn, strSQL)
      Debug.Print rs(0)     'Print Row 1, Col 1 to Debug window
      End Sub
   
      Private Sub Command2_Click()
      'This example executes an action query but does not return
      'a recordset.
      Dim strCn As Variant, strSQL As Variant
      strCn = "dsn=pubs;Username=<username>;PWD=<strong password>"
      strSQL = "Update authors Set au_fname = 'Jon' Where au_lname" _
      & " Like 's%'"
      df.Query strCn, strSQL
      End Sub
    
   					

Note You must change the DSN to match a System DSN on your IIS/ASP/RDS server before you continue. You also must change the IIS/RDS server name.

1. Start the program or press the F5 key.
2. Click the Command1 button to execute the RDS code that returns a recordset. If it executes successfully, row 1, column 1 will be output to the Debug Immediate window.
3. Click the Command2 button to execute the action query that updates the au_fname column in the authors table. No data is returned from the action query.