如何使用belongs_to的兩個屬性將ActiveRecord模型連接到另一個模型

Question

請幫我解決下面的問題。

我試圖連接兩個activerecord模型，其中一個模型（Job）有兩個屬性，hiring_company_id和advertising_company_id，它引用了另一個模型（CompanyBase）。但是，我收到一個SQL錯誤，沒有這樣的表：main.hiring_companies：，當保存工作模型。

我寫的代碼這樣，我省略了一些屬性更簡潔：

工作型號：

class Job < ApplicationRecord 
    has_paper_trail on: [:update, :destroy] 
    belongs_to :job_type, inverse_of: :jobs 
    belongs_to :advertising_company, class_name: 'CompanyBase', foreign_key: :advertising_company_id, inverse_of: :jobs 
    belongs_to :hiring_company, class_name: 'CompanyBase', foreign_key: :hiring_company_id, inverse_of: :jobs 
    validates :hide_advertising_company, inclusion: { in: [true, false], message: :must_be_true_or_false }, if: lambda { advertising_company.present? } 
end 

的ActiveRecord遷移的工作模式：

class CreateJobs < ActiveRecord::Migration[5.1] 
    def change 
    create_table :jobs do |t| 
     t.belongs_to :job_type, foreign_key: true 
     t.belongs_to :advertising_company, class_name: 'CompanyBase', foreign_key: :advertising_company_id 
     t.belongs_to :hiring_company, class_name: 'CompanyBase', foreign_key: :hiring_company_id 
     t.timestamps 
    end 
    end 
end 

CompanyBase模型：

class CompanyBase < ApplicationRecord 
    has_paper_trail on: [:update, :destroy] 
    has_many :jobs, foreign_key: :advertising_company_id, dependent: :destroy, inverse_of: :company_base 
    has_many :jobs, foreign_key: :hiring_company_id, dependent: :destroy, inverse_of: :company_base 
end 

當我創建Job對象並嘗試保存它時，出現以下sql錯誤：ActiveRecord :: StatementInvalid：SQLite3 :: SQLException：no such table：main.hiring_companies。但是我沒有得到與advertising_company屬性相同的錯誤，並且代碼是相同的。我做錯了什麼？

irb(main):018:0> jb.save! 
    (0.3ms) begin transaction 
    SQL (1.6ms) INSERT INTO "jobs" ("country_w_id", "job_type_id", "advertising_company_id", "hiring_company_id", "position", "handicapped_only", "hide_advertising_company", "hide_hiring_company", "hide_salary", "description", "requisites", "salary_from", "salary_to", "work_time", "created_at", "updated_at") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) [["country_w_id", 1], ["job_type_id", 1], ["advertising_company_id", 1], ["hiring_company_id", 1], ["position", "Gerente"], ["handicapped_only", "f"], ["hide_advertising_company", "f"], ["hide_hiring_company", "f"], ["hide_salary", "f"], ["description", "descrição"], ["requisites", "requisitos"], ["salary_from", 10], ["salary_to", 100], ["work_time", "full"], ["created_at", "2017-08-06 19:03:18.295519"], ["updated_at", "2017-08-06 19:03:18.295519"]] 
    (0.1ms) rollback transaction 
ActiveRecord::StatementInvalid: SQLite3::SQLException: no such table: main.hiring_companies: INSERT INTO "jobs" ("country_w_id", "job_type_id", "advertising_company_id", "hiring_company_id", "position", "handicapped_only", "hide_advertising_company", "hide_hiring_company", "hide_salary", "description", "requisites", "salary_from", "salary_to", "work_time", "created_at", "updated_at") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) 
     from (irb):18 
i 

感謝，

何塞·費爾南多

Answer 1

我已經解決了這個問題，我在這裏張貼的答案，人們類似的問題。 該問題是由錯誤的關係名稱引起的。正確的方法是：

工作模式：

class Job < ApplicationRecord 
    has_paper_trail on: [:update, :destroy] 
    belongs_to :job_type, inverse_of: :jobs 
    belongs_to :advertising_company, class_name: 'CompanyBase', inverse_of: :jobs 
    belongs_to :hiring_company, class_name: 'CompanyBase', inverse_of: :jobs 
    validates :hide_advertising_company, inclusion: { in: [true, false], message: :must_be_true_or_false }, if: lambda { advertising_company.present? } 
end 

的ActiveRecord遷移的工作模式：

class CreateJobs < ActiveRecord::Migration[5.1] 
    def change 
    create_table :jobs do |t| 
     t.belongs_to :job_type, foreign_key: true 
     t.belongs_to :advertising_company, class_name: 'CompanyBase', index: true 
     t.belongs_to :hiring_company, class_name: 'CompanyBase', index: true 
     t.timestamps 
    end 
    end 
end 

CompanyBase型號：

class CompanyBase < ApplicationRecord 
    has_paper_trail on: [:update, :destroy] 
    has_many :jobs, dependent: :destroy, inverse_of: :advertising_company 
    has_many :jobs, dependent: :destroy, inverse_of: :hiring_company 
end 

最好的問候，

何塞費爾南多