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• master
• 10-user

Burada STI'den konuşacağız fakat MTI'de var http://mediumexposure.com/multiple-table-inheritance-active-record/

STI (Single Table Inheritance)

Gerçeklemeye konu olan nesne yapısı/ilişkisi,

Console,

> FullTimeEmployee.create!(:name => "Jim", :salary => "10,000", :hours => "37")
> TempEmployee.create!(:name => "John", :salary => "15,000", :duration => "5")
> StudentEmployee.create!(:name => "Joe", :salary => "20,000",
    :university => "Queens University, Belfast")
> y Employee.all
  Employee Load (0.2ms)  SELECT "employees".* FROM "employees"
---
- !ruby/object:FullTimeEmployee
  attributes:
    id: 1
    name: Jim
    salary: '10,000'
    hours: '37'
    duration:
    university:
    type: FullTimeEmployee
    created_at: 2012-05-24 08:36:18.960678000 Z
    updated_at: 2012-05-24 08:36:18.960678000 Z
- !ruby/object:TempEmployee
  attributes:
    id: 2
    name: John
    salary: '15,000'
    hours:
    duration: '5'
    university:
    type: TempEmployee
    created_at: 2012-05-24 08:37:22.752618000 Z
    updated_at: 2012-05-24 08:37:22.752618000 Z
- !ruby/object:StudentEmployee
  attributes:
    id: 3
    name: Joe
    salary: '20,000'
    hours:
    duration:
    university: Queens University, Belfast
    type: StudentEmployee
    created_at: 2012-05-24 08:37:54.233763000 Z
    updated_at: 2012-05-24 08:37:54.233763000 Z
=> nil

Extra

İki STI modeli arasında haberleşme kurulumu nasıl? Bunun gerçeklemesi ilgili commit te yapıldı.

Elimizde User modeli var STI üzerinden Editor vd:

Ayrıca Question modelinde STI üzerinden Qumcq vd:

Bunları model üzerinde şöyle bağladım,

    class Qumcq < Question
            has_and_belongs_to_many :editors, class_name: 'User',
                    join_table: 'users_questions',
                    association_foreign_key: 'user_id', foreign_key: 'question_id'
    end

    class Editor < User
            has_and_belongs_to_many :questions, class_name: 'Question',
                    join_table: 'users_questions',
                    association_foreign_key: 'question_id', foreign_key: 'user_id'
    end

Test,

    > Qumcq.last.editors