Querying the database with the Recordset object

The ADO Recordset object represents the result set of a query. You can use it to view data from a database.

Sample code

You can try this routine by placing a command button named cmdQuery on a form and pasting the routine into its Click event. Run the program and click the button to connect, display a message in the database server messages window, execute a query and display the first few rows in windows, and then disconnect.

Private Sub cmdQuery_Click( _
        ByVal eventSender As System.Object, _
        ByVal eventArgs As System.EventArgs) _
        Handles cmdQuery.Click

    ' Declare variables
    Dim i As Integer
    Dim myConn As New ADODB.Connection
    Dim myCommand As New ADODB.Command
    Dim myRS As New ADODB.Recordset
    
    On Error GoTo ErrorHandler
    
    ' Establish the connection
    myConn.Provider = "SAOLEDB"
    myConn.ConnectionString = _
        "Data Source=SQL Anywhere 12 Demo"
    myConn.CursorLocation = _
        ADODB.CursorLocationEnum.adUseServer
    myConn.Mode = _
        ADODB.ConnectModeEnum.adModeReadWrite
    myConn.IsolationLevel = _
        ADODB.IsolationLevelEnum.adXactCursorStability
    myConn.Open()
    
    'Execute a query
    myRS = New ADODB.Recordset
    myRS.CacheSize = 50
    myRS.let_Source("SELECT * FROM Customers")
    myRS.let_ActiveConnection(myConn)
    myRS.CursorType = ADODB.CursorTypeEnum.adOpenKeyset
    myRS.LockType = ADODB.LockTypeEnum.adLockOptimistic
    myRS.Open()
    
    'Scroll through the first few results
    myRS.MoveFirst()
    For i = 1 To 5
        MsgBox(myRS.Fields("CompanyName").Value, _
            MsgBoxStyle.Information)
        myRS.MoveNext()
    Next 
    
    myRS.Close()
    myConn.Close()
    Exit Sub
    
ErrorHandler: 
    MsgBox(ErrorToString(Err.Number))
    Exit Sub
End Sub

Notes

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