设计字段链接到另一个表中的记录

Question

我正在为航空公司路线定义数据结构。

预期用法将是那样的

Route.find(1).from_airport # NRT
Route.find(1).to_airport # KIX
Route.find(2).from_airport # NRT
Route.find(2).to_airport # TPE

但是，我不想在from_airport字段或to_airport字段中定义字符串值。

机场数据应保留在机场表中。

我如何在Ruby on Rails中定义它？

它是否属于Route表上的has_one逻辑，并且没有机场的belongs_to逻辑。

型号：路线（在我看来）

has_one :from_airport, foreign_key: "id??", class_name: "Route"
has_one :to_airport, foreign_key: "id??", class_name: "Route"

机场表

id:1 name: NRT, city: TOKYO, country: JAPAN
id:2 name: KIX, city: OSAKA, country: JAPAN

路线表

from_airport:  # it should NOT be a string, it should refers to a record in Airports table eg: airport (id:1)
to_airport:  # it should NOT be a string, it should refers to a record in Airports table eg: airport (id:1)

Answer 1

这是你要找的吗？

# routes.rb
belongs_to :from_airport, foreign_key: :from_airport_id, class_name: "Airport", primary_key: :id
belongs_to :to_airport, foreign_key: :to_airport_id, class_name: "Airport", primary_key: :id