Add billing_addresses.

app/models/billing_address.rb

@@ -0,0 +1,2 @@
+class BillingAddress < ActiveRecord::Base
+end

db/migrate/20100707090604_create_billing_addresses.rb

@@ -0,0 +1,23 @@
+class CreateBillingAddresses < ActiveRecord::Migration
+  def self.up
+    create_table :billing_addresses do |t|
+      t.string :name
+      t.string :address1
+      t.string :address2
+      t.string :city
+      t.string :state
+      t.string :country
+      t.string :zip
+      t.string :phone
+
+      t.timestamps
+    end
+
+    add_column :orders, :billing_address_id, :integer
+  end
+
+  def self.down
+    remove_column :orders, :billing_address_id
+    drop_table :billing_addresses
+  end
+end