很多时候，轨道中的Mongodb协会无法找到数据，但有时会工作

Here i have Review module

这里我有Review模块

class Review
  include Mongoid::Document
  include Mongoid::Timestamps
  belongs_to :job

  has_many :options, :class_name => "Option"
  accepts_nested_attributes_for :options, allow_destroy: true
end
clas