private void Button1_Click(System.Object sender, System.EventArgs e) { //Here In "Students" Table "StudentID" Is Primary Key & It Will Do Relation With "Results" Table's "StudentID" Field As Foreig Key... DataSet ds = new DataSet(); DataRelation StudentsResultsRelation = new DataRelation("StudentsResults", ds.Customers.Columns("StudentID"), ds.Orders.Columns("StudentID")); //Add New Created Relation... ds.Relations.Add(StudentsResultsRelation); }