private void detach_OrderItems(OrderItem entity)
		{
			this.SendPropertyChanging();
			entity.Product = null;
		}
		private void attach_OrderItems(OrderItem entity)
		{
			this.SendPropertyChanging();
			entity.Product = this;
		}
 partial void UpdateOrderItem(OrderItem instance);
 partial void DeleteOrderItem(OrderItem instance);
 partial void InsertOrderItem(OrderItem instance);