migration_n_plus_one.rb

class CreateUsers < ActiveRecord::Migration[5.1]
  def change
    create_table :users do |t|
      t.string :name

      t.timestamps
    end
  end
end


class CreateAddresses < ActiveRecord::Migration[5.1]
  def change
    create_table :addresses do |t|
      t.text :street
      t.string :city
      t.string :state
      t.string :zipcode
      t.integer :user_id

      t.timestamps
    end

    add_foreign_key :addresses, :users
  end
end