在Mongoid中嵌入带有belong_to关联的文档 [英] Embeded document with belong_to association in Mongoid

问题描述

我有像波纹管这样的模型.我想通过来宾列表"为具有不同状态的用户查询事件.如果客人输入的清单没有错，则应将其嵌入事件中吗?如果我的模型设计错误，我会开放其他解决方案.

I have models like bellow. i want to query events for user with different kind of statuses by guests 'list'. If am not wrong guests list should be embeded in events? If my model design are wrong i`m open for different solution.

class User
  include Mongoid::Document

end

class Events
  include Mongoid::Document

  embeds_many :guests
end

Class Guests
  include Mongoid::Document

  embed_in :event
  belongs_to :user

  field :status

end

推荐答案

模型结构是错误的，因为在Mongo中，您仅将信息保留在仅父文档中需要的嵌入式文档中.

The model structure is wrong as in Mongo you only keep the information in embedded documents which are required only in parent document.

如果在来宾中只有状态字段，则可以尝试此操作，例如，两种状态类型存在或不存在

If in guests you have only status field, then you can try this,e.g., two status type present or not present

class User
  include Mongoid::Document
  has_and_belongs_to_belongs_to :event, :inverse_of => "present_guests"
  has_and_belongs_to_belongs_to :event, :inverse_of => "not_present_guests"
end

class Event
  include Mongoid::Document
  has_and_belongs_to_many :present_guests, :class_name => "User", :inverse_of => "present_guests"
  has_and_belongs_to_has_many :not_present_guests, :class_name => "User", :inverse_of => "not_present_guests"
end

然后您可以使用类似状态的查询

then you can query with the status like

Event.first.present_guests

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