How To Use an RDO Prepared Statement to Find a Single Record

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Step-By-Step Example

1. Start a new project in Visual Basic. Form1 is created by default. Add a CommandButton and a text box. Accept the default names for all.
2. Make sure a reference to the Microsoft Remote Data Object library has been established. In Visual Basic 4.0, you can establish the reference by clicking References from the Tools menu. In Visual Basic 5.0, click References from the Project menu.
3. Add the following code to the General Declarations section of Form1:

         Option Explicit
         Dim ps As rdoPreparedStatement
         ' Dim as rdoQuery    rdoquery replace PreparedStatement
         ' in VB5 and VB6
         Dim conn As rdoConnection
         Dim rs As rdoResultset
   
         Private Sub Form_Load()
             With rdoEnvironments(0)
                 .CursorDriver = rdUseOdbc
            Set conn = .OpenConnection("", rdDriverNoPrompt, False, _
                 "driver={SQL Server};
                 server=Myserver;uid=MyUID;pwd=Mypwd;database=pubs")
             End With
             Set ps = conn.CreatePreparedStatement("", _
          '   CreateQuery replaces CreatePreparedStatement in VB5 and VB6
          '   Set ps = conn.CreateQuery("", _
                           "select au_lname from authors where au_lname = ?")
         End Sub
   
         Private Sub Command1_Click()
             ps.rdoParameters(0) = Text1.Text
             If rs Is Nothing Then
                 Set rs = ps.OpenResultset(rdOpenKeyset)
             Else
                 rs.Requery
             End If
             If Not rs.EOF Then
                 Msgbox rs!au_lname
             Else
              Msgbox "No record match."
             End If
         End Sub
   
         Private Sub Form_Unload(Cancel As Integer)
             rs.Close
             ps.Close
             conn.Close
         End Sub
   
   						

4. Make sure you have an appropriate ODBC data source, user ID, and password, then press F5 to run the program. Type your search criteria in Text1 (for example, "White"), and click the CommandButton. A message box will appear with either the record you are searching for if there is a match, or with a message "No record match" if there is no match.