Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click 'Here In "Customers" Table "CustomerID" Is Primary Key & It Will Do Relation With "Order" Table's "CustomerID" Field As Foreig Key... Dim ds As New DataSet() Dim CustomersOrdersRelation As New DataRelation("CustomersOrders", ds.Customers.Columns("CustomerID"), ds.Orders.Columns("CustomerID")) 'Add New Created Relation... ds.Relations.Add(customersOrdersRelation) End Sub