加入 Rails 中的两个表，被称为 has_one: ".. ",class_name:"..."

Question

class Transport::Vehicle < ApplicationRecord
    has_one :driver, class_name: "Admin", foreign_key: "driver_id"
end 

Transport::Vehicle.joins(:driver) 

生成以下 SQL 查询

SELECT  "transport_vehicles".* FROM "transport_vehicles" INNER JOIN "admins" ON "admins"."driver_id" = "transport_vehicles"."id" AND "admins"."deleted_at" IS NULL LIMIT 

但应该是

SELECT  "transport_vehicles".* FROM "transport_vehicles" INNER JOIN "admins" ON "admins"."id" = "transport_vehicles"."id" AND "admins"."deleted_at" IS NULL LIMIT 

我怎样才能得到 admin.id 而不是 admins.driver_id ??

Answer 1

由于您的外键在 Transport::Vehicle class 上，您应该使用 belongs_to 而不是 has_one.