如何初始化ActiveRecord Tableless模型？

问题描述

在我的模型中，我有：

我使用Ruby on Rails 3和我想初始化一个ActiveRecord Tableless模型。

  class Account< ActiveRecord :: Base 
 
＃以下ActiveRecord Tableless Model语句来自http://codetunes.com/2008/07/20/tableless-models-in-rails/ 
 def self。 columns（）
 @columns || = []; 
 end 
 
 def self.column（name，sql_type = nil，default = nil，null = true）
 columns< ActiveRecord :: ConnectionAdapters :: Column.new（name.to_s，default，sql_type.to_s，null）
 end 
 
 attr_reader：id，
：firstname，
 ：lastname，
 
 def initialize（attributes = {}）
 @id = attributes [：id] 
 @firstname = attributes [：firstname] 
 @lastname = attributes [：lastname] 
 end 
 end 
  

示例在application_controller.rb文件中，我执行：

  @new_account = Account.new（{：id =>1 ，：firstname =>Test name，：lastname =>Test lastname}）
  

@new_account 变量的debug\inspect输出为

 ＃< Account> 
  

为什么？我应该如何正确地初始化ActiveRecord Tableless模型并使其工作？

解决方案

将如下所示：

  class Account< ActiveRecord :: Base 
 
 class_inheritable_accessor：columns 
 
 def self.columns（）
 @columns || = []; 
 end 
 
 def self.column（name，sql_type = nil，default = nil，null = true）
 columns< ActiveRecord :: ConnectionAdapters :: Column.new（name.to_s，default，sql_type.to_s，null）
 end 
 
 column：id，：integer 
 column：firstname，： string 
 column：lastname，：string 
 
 end 
  

然后：

  @new_account = Account.new（{：id =>1，：firstname => name，：lastname =>Test lastname}）
  

？

I am using Ruby on Rails 3 and I would like to inizialize an ActiveRecord Tableless Model.

In my model I have:

class Account < ActiveRecord::Base

  # The following ActiveRecord Tableless Model statement is from http://codetunes.com/2008/07/20/tableless-models-in-rails/
  def self.columns() 
    @columns ||= [];
  end

  def self.column(name, sql_type = nil, default = nil, null = true)
    columns << ActiveRecord::ConnectionAdapters::Column.new(name.to_s, default, sql_type.to_s, null)
  end

  attr_reader :id,
              :firstname,
              :lastname,

  def initialize(attributes = {})
    @id = attributes[:id]
    @firstname = attributes[:firstname]
    @lastname = attributes[:lastname]
  end
end

If in a controller, for example in the application_controller.rb file, I do:

@new_account = Account.new({:id => "1", :firstname => "Test name", :lastname => "Test lastname"})

a debug\inspect output of the @new_account variable is

"#<Account >"

Why? How I should inizialize properly that ActiveRecord Tableless Model and make it to work?

解决方案

According to that blog post it would have to look like this:

class Account < ActiveRecord::Base

  class_inheritable_accessor :columns

  def self.columns() 
    @columns ||= [];
  end

  def self.column(name, sql_type = nil, default = nil, null = true)
    columns << ActiveRecord::ConnectionAdapters::Column.new(name.to_s, default, sql_type.to_s, null)
  end

  column :id, :integer
  column :firstname, :string
  column :lastname, :string

end

And then:

@new_account = Account.new({:id => "1", :firstname => "Test name", :lastname => "Test lastname"})

Did you already try it like that?

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