Rails，将has_and_belongs_to_many与抽象模型一起使用

Question

I have abstract model Detail that has child models like Carcass , Basis . Also i have User model. Can I use has_and_belongs_to_many association between User and Detail ? Could it be inherited to child models? Or do I need to use that association between User and each model of Detal ?

The main goal is to create many-to-many relationship.

I am using rails 4.

Answer 1

Sure, has_and_belongs_to_many can be defined only in parent class. Child classes will inherit this property

Don't forget to create the respective tables to many to many relationships ( carcass_users and basis_users ) with:

rails g migration CreateCarcassUsers

Inside your migration:

class CreateCarcassUsers < ActiveRecord::Migration
  def change
    create_table :carcass_users do |t|
      t.integer :carcass_id
      t.integer :user_id
      t.timestamps
    end
  end
end