private static void DeleteCustomer(string id)
        {
            var customer = (from c in northwind.Customers
                            where c.CustomerID == id
                            select c).Single();

            northwind.Orders.DeleteAllOnSubmit(customer.Orders);
            try
            {
                northwind.SubmitChanges();
                Console.WriteLine(String.Format("Customer {0} deleted", id));
            }
            catch (ChangeConflictException)
            {
                northwind.ChangeConflicts.ResolveAll(RefreshMode.KeepChanges);
            }

            northwind.Customers.DeleteOnSubmit(customer);
            try
            {
                northwind.SubmitChanges();
                Console.WriteLine(String.Format("Customer {0} deleted", id));
            }
            catch (ChangeConflictException)
            {
                northwind.ChangeConflicts.ResolveAll(RefreshMode.KeepChanges);
            }
        }