Generate models with associations using rails generators, enabling custom class_name, foreign keys, and indices.

rails custom name associations

Here's how it flows:  
  
1. Create models:  
  
  ```
  rails g model User name --no-test-framework --no-assets  
  rails g model Post content --no-test-framework --no-assets  
  rails g model Address city --no-test-framework --no-assets  
  ```
  
2. Create and migrate db:  
  
  ```
  rake db:create db:migrate
  ```
  
  (`db:setup` does not create a new `schema.rb`, which is problematic at resetting the db so it's better to have this habit of using the two above commands. `rake db:reset` is in this case also a worse choice as it does not run migrations.)  
  
3. Modify associations in models:  
  
  ```
  #user.rb  
  has_many :posts, foreign_key: :author_id, dependent: :destroy  
has_one :address, foreign_key: :owner_id  
  ```
  
  ```  
  #post.rb  
  belongs_to :author, class_name: 'User'
  ```
  
  ```
  #address.rb
  belongs_to :owner, class_name: 'User'
  ```
  
4. Add references in db:  
  
  `rails g migration AddReferences`:  

  ```
  def change
    add_reference :posts, :author, index: true
    add_reference :addresses, :owner, index: true
  end
  ```
  
5. Add foreign keys:  
  
  `rails g migration AddForeignKeys`:  
  ```
  def change
    add_foreign_key :posts, :users, column: :author_id
    add_foreign_key :addresses, :users, column: :owner_id
  end
  ```  
  
6. Migrate and check if everything works fine:  
  
  ```
  rake db:migrate
  rails c
  User.first
  Post.first
  Address.first
  User
  Post
  Address
  User.create!(name: 'Maciek')
  Post.create!(content: 'First post', author: User.first)
  Address.create!(city: 'Mikolow', owner: User.first)
  Post.first.author
  Address.first.owner
  User.first.posts
  User.first.address
  ```