Rails两个模型之间的多个关联

Question

我在Rails 3应用程序中有Flight、Person和Glider模型。我定义了自定义关系，因为我需要多个外键引用航班表中的Person。关联只能单向工作。

class Flight < ActiveRecord::Base
  belongs_to :pilot, :class_name => "Person"
  belongs_to :instructor, :class_name => "Person"
  belongs_to :towplane_pilot, :class_name => "Person"
  belongs_to :airplane_instructor, :class_name => "Person"
  belongs_to :glider
  belongs_to :rep_glider, :class_name => "Glider"
  belongs_to :departure_airfield, :class_name => "Airfield"
  belongs_to :arrival_airfield, :class_name => "Airfield"
end
class Glider < Aircraft
  has_many :flights
  has_many :replaced_flights, :foreign_key => "rep_glider_id", :class_name => "Flight"
end
class Person < ActiveRecord::Base
  has_many :flights, :foreign_key => "pilot_id", :class_name => "Flight"
  has_many :instructed_flights, :foreign_key => "instructor_id", :class_name => "Flight"
  has_many :towed_flights, :foreign_key => "towplane_pilot_id", :class_name => "Flight"
  has_many :instructed_towing_flights, :foreign_key => "airplane_instructor_id", :class_name => "Flight"
end

---

---

####What works#####
Flight.first.glider
Flight.first.rep_glider
Flight.first.pilot 
Flight.first.instructor 
Flight.first.towplane_pilot
Flight.first.airplane_instructor
Glider.first.flights 
Glider.first.replaced_flights    
####What doesn't work#### ----> NoMEthodError 'match'
Person.first.flights
Person.first.instructed_flights
Person.first.towed_flights.
Person.first.instructed_towing_flights

我几乎在那里，但我不明白Glider.first.flights是如何工作的，而Person.first.flights没有。

更新:与"机场"工程的关联…所以我不知道为什么它不能用'Person'

class Airfield < ActiveRecord::Base
  has_many :takeoff_flights, :foreign_key => "departure_airfield_id", :class_name => "Flight"
  has_many :grounded_flights, :foreign_key => "arrival_airfield_id", :class_name => "Flight"
end
###Works Correctly
Airfield.first.takeoff_flights 
Airfield.first.grounded_flights
Flight.first.departure_airfield
Flight.first.arrival_airfield

Answer 1

你的飞行员有类型吗?像一个pilot_type列?我也刚刚开始阅读这些类型的模式，幸运的是，它仍然有点新鲜(希望)。如果我错了，请纠正我!:))

您需要此处讨论的多态模式:

http://asciicasts.com/episodes/154-polymorphic-association

Answer 2

我被告知这些模型之间的关联是正确设置的。

我在航班表中添加了一条新记录，现在这个新记录和之前的所有记录的关联都可以正常工作。我不太确定它现在是如何工作的，但它确实是。