轨道上的红宝石 - 使用 Mongoid 进行优化"serialize"

Question

我有这个对象：

class MessageSetting
  include Mongoid::Document
  include Mongoid::Timestamps::Created
  #relationships
  embedded_in :user
  field :when_new_order, :type => Boolean, :default => "true"
  field :when_cancel_order, :type => Boolean, :default => "true"
  field :when_expire_order, :type => Boolean, :default => "true"
  field :when_reject_order, :type => Boolean, :default => "true"
  field :when_accept_order, :type => Boolean, :default => "true"
  field :when_in_progress_overtime, :type => Boolean, :default => "true"
  field :when_is_canceled_due_overtime, :type => Boolean, :default => "true"
  field :when_deliver_order, :type => Boolean, :default => "true"
  field :when_order_complete, :type => Boolean, :default => "true"
  field :when_open_dispute, :type => Boolean, :default => "true"
  field :when_buyer_request_refund, :type => Boolean, :default => "true"
  field :when_seller_made_refund, :type => Boolean, :default => "true"
  field :when_seller_made_dispute_response, :type => Boolean, :default => "true"
  field :when_buyer_made_dispute_response, :type => Boolean, :default => "true"
  attr_accessible :when_new_order, :when_cancel_order, :when_expire_order, :when_reject_order,
                  :when_accept_order, :when_in_progress_overtime, :when_is_canceled_due_overtime,
                  :when_deliver_order, :when_deliver_order, :when_order_complete, :when_open_dispute,
                  :when_buyer_request_refund, :when_seller_made_refund, :when_seller_made_dispute_response, :when_buyer_made_dispute_response
  def active_new_order?
   when_new_order?
  end
  def active_when_cancel_order?
   when_cancel_order?
  end
  def active_when_expire_order?
   when_expire_order?
  end
  def active_when_reject_order?
   when_reject_order?
  end
  def active_when_accept_order?
   when_accept_order?
  end
  def active_when_in_progress_overtime?
   when_in_progress_overtime?
  end
  def active_when_is_canceled_due_overtime?
   when_is_canceled_due_overtime?
  end
  def active_when_deliver_order?
   when_deliver_order?
  end
  def active_when_order_complete?
   when_order_complete?
  end
  def active_when_open_dispute?
   when_open_dispute?
  end
  def active_when_buyer_request_refund?
   when_buyer_request_refund?
  end
  def active_when_seller_made_refund?
   when_seller_made_refund?
  end
  def active_when_seller_made_dispute_response?
   when_seller_made_dispute_response?
  end
  def active_when_buyer_made_dispute_response?
   when_buyer_made_dispute_response?
  end
end

我知道我可以用 mongoid 进行"序列化"：

field :status_message_setting, type: Hash

那么我可以：

m = MessageSetting.new
m.status_message_setting = {:when_new_order => true, :when_cancel_order => false, ...}
m.save

我需要知道参考性能、最佳实践和可用资源，最好使用此模型hash"序列化"？

Answer 1

并非所有 Ruby 类都可以开箱即用地序列化，但幸运的是，哈希是可以序列化的类之一。因此，没有理由为它们编写自己的序列化。但是，如果您这样做并且速度有所提高，那将是最小的。序列化主要用于持久保存具有自定义数据类型的字段。

它不会加快数据库速度，但如果您真的想节省空间，您可以为全布尔哈希创建自定义类型，并将哈希序列化为位码。您将创建自定义类并定义mongoize实例方法，并根据要序列化数据的方式mongoize、demongoize和evolve类方法。是的，这绝对是可能的。然而，在实践中，实现起来很麻烦，并且不会为您节省那么多空间，除非您的哈希值与模型中的其他数据相比很大。

对于您的情况，节省空间的更简单方法是像这样缩短所有字段名称：

field :wno, as: :when_new_order, :type => Boolean, :default => "true"
field :wco, as: :when_cancel_order, :type => Boolean, :default => "true" ...

由于数据库中存储的每个文档的字段名称都是重复的，因此长字段名称将开始占用大量额外空间。由于您传递了别名，例如 :when_new_order，那么您的模型将像以前一样运行。