i have an Order model and a table for addresses. i was trying to use single table inheritance so that i can store the addresses in the same table.
here is my order model:
class Order < ActiveRecord::Base
has_one :billing_address, :class_name => 'BillingAddress', :foreign_key => 'order_id' has_one :shipping_address, :class_name => 'ShippingAddress', :foreign_key => 'order_id' end
and the address model:
class Address < ActiveRecord::Base end
class BillingAddress < Address belongs_to :order, :class_name => 'Order' end
class ShippingAddress < Address belongs_to :order, :class_name => 'Order' end
everything appears to be working fine, unless i try and do something like this:
my_order.billing_address.create(...)
i get this in the console:
NoMethodError: You have a nil object when you didn't expect it! You might have expected an instance of ActiveRecord::Base. The error occurred while evaluating nil.create
however, if i create an address this way:
BillingAddress.create(....... :order => my_order) it works fine. i can even use order.billing_address and it will pull up the right record.
is this right, or did i set up the relationships wrong?
