heroku和db迁移

class AddExpMonthAndExpYearToOrder < ActiveRecord::Migration 
    def self.up 
    add_column :orders, :exp_month, :integer 
    add_column :orders, :exp_year, :integer 
    end 

    def self.down 
    remove_column :orders, :exp_month 
    remove_column :orders, :exp_year 
    end 
end

有此迁移，在heroku上运行它，但没有任何更改。新字段不会出现在表格中。不知道哪里出了问题heroku和db迁移

Ruby console for sample.heroku.com 
>> Order 
=> Order(id: integer, ship_address: string, city: string, state: string, zip: string, cc_number: string, telephone: string, cart_id: integer, created_at: datetime, updated_at: datetime) 
>> exit 
petya:geomarket > heroku rake db:migrate 
(in /app) 
== AddExpMonthAndExpYearToOrder: migrating =================================== 
-- add_column(:orders, :exp_month, :integer) 
    -> 0.0025s 
-- add_column(:orders, :exp_year, :integer) 
    -> 0.0017s 
== AddExpMonthAndExpYearToOrder: migrated (0.0044s) ========================== 

petya:geomarket > heroku console 
Ruby console for sample.heroku.com 
>> Order 
=> Order(id: integer, ship_address: string, city: string, state: string, zip: string, cc_number: string, telephone: string, cart_id: integer, created_at: datetime, updated_at: datetime)

在我的本地机器上一切正常。试图重新启动，没有帮助。

来源

2011-05-22 Petya petrov

试试重装！从控制台。 – 2011-05-22 15:43:36

重新加载没有帮助 – 2011-05-22 15:47:13

即时想要保留我的数据加上即时消息不知道这种方法将工作 – 2011-05-22 15:48:04