ruby-on-rails – 单表继承在Rails 4 app中不起作用 – ActiveRe

主模型称为Order,它继承自ActiveRecord :: Base.这是它的样子：

class Order < ActiveRecord::Base
  TYPES = %w(remote local)

  scope :remotes,-> { where(type: 'remote') }
  scope :locals,-> { where(type: 'local') }
end

其他两个模型位于模型/订单的文件夹中,它们被称为远程和本地,它们都从Order继承

订单迁移文件如下所示：

def change
  create_table :orders do |t|
    t.string :source_url,null: false
    t.string :final_url,null: false

    t.string :type

    t.string :category

    t.timestamps
  end
end

我还确保通过执行以下操作将模型/订单目录包含在Rails中：

config.autoload_paths += Dir[Rails.root.join('app','models','{**}')]

现在,当我使用清空的数据库登录控制台并运行Order.all时,一切都很好,我得到一个空关系对象.但是在我创建第一个Remote对象并尝试再次运行Order.all后,我收到以下错误：

>> Order.all
Order Load (1.0ms)  SELECT "orders".* FROM "orders"
ActiveRecord::SubclassNotFound: The single-table inheritance mechanism failed to locate
the subclass: 'Remote'. This error is raised because the column 'type' is reserved
for storing the class in case of inheritance. Please rename this column if you didn't
intend it to be used for storing the inheritance class or overwrite
Order.inheritance_column to use another column for that information.

这里发生了什么？我做错了什么？

提前致谢.