Private Sub TableRelation()
 
    Dim dt1 As New DataTable
 
    dt1.Columns.Add("RPM", GetType(Integer))
    dt1.Columns.Add("Sound", GetType(String))
 
    With dt1.Rows
         .Add(1000, "surr")
         .Add(1200, "brumm")
         .Add(1500, "brumm")
         .Add(2500, "pfeif")
         .Add(4000, "rassel")
         .Add(5000, "schepper")
         .Add(6000, "kaputt")
    End With
 
    dt1.PrimaryKey = {dt1.Columns("RPM")} 'eindeutiger Schlüssel
 
    Dim dt2 As New DataTable
 
    dt2.Columns.Add("RPM_2", GetType(Integer))
    dt2.Columns.Add("Sound", GetType(String))
 
    With dt2.Rows
       .Add(2500, "brumm")
       .Add(4000, "quietsch")
       .Add(6000, "jaul")
       .Add(1500, "surr")
       .Add(1200, "surr")
       .Add(1000, "surr")
    End With
 
    dt2.PrimaryKey = {dt2.Columns("RPM_2")} 'eindeutiger Schlüssel
 
    'gemeinsames Dataset
    Dim ds As New DataSet("RPM_Set")
 
    ds.Tables.Add(dt1) : ds.Tables.Add(dt2)
 
    'Beziehung zwischen Tabellen über eine Datarelation
    Dim dr As New DataRelation _
        ("RPM_Relation", dt1.Columns("RPM"), dt2.Columns("RPM_2"), True)
    ds.Relations.Add(dr)
 
 
    For r1 As Integer = 0 To dt1.Rows.Count - 1
        'korrespondierende Zeilen zur r-Zeile in dt1 '
        'per Relation aus dt2 abfragen
        Dim rows_in_dt2 As DataRow() = dt1.Rows(r1).GetChildRows(dr)
        If rows_in_dt2.Count = 0 Then
           Console.WriteLine _
           (dt1.Rows(r1)("RPM").ToString & _
            " keine Entsprechung in Tabelle 2")
        Else
           For rc As Integer = 0 To rows_in_dt2.Count - 1
              Console.WriteLine _
              (dt1.Rows(r1)("RPM").ToString & "--->" & _
               rows_in_dt2(rc)("Sound").ToString)
           Next rc 'Childrows zur row r1 ind dt1
        End If
    Next r1
 
End Sub