Rails ActiveRecord协会

Question

我有routes表，字段from_airport_id和to_airport_id。

比方说：

route = Route.find(1) 

的问题是：如何定义ActiveRecord关联，那route.from_airport就等于Airport.find（route.from_airport_id）和route.to_airport = Airport.find（路线.to_airport_id）？

换句话说：

from_airport_id => airport.id

to_airport_id => airport.id

我猜，查询应该是：

route = Route.find(1).includes(:airports) 

但是怎么办我一次从同一张表中选择两条记录？

Answer 1

has_many :from_airports, :class_name => "AirPort", 
:foreign_key => "from_airport_id" 


has_many :to_airports, :class_name => "AirPort", 
:foreign_key => "to_airport_id"