ActiveRecord

advanced_ar.rb

# Study has_many, belongs_to methods (10 or so)

ActiveRecord::Migration.create_table :followings do |t|
  t.belongs :follower
  t.belong :stalked
end

ActiveRecord::Migrator.up "db/migrate"

class User < ActiveRecord::Base
  # I follow people.
  has_many :followings, foreign_key: "follower_id"
  has_many: :stalked_users, through: :followings, source: :stalked
  
  # People follow me.
  has_many :opposite_followings, class_name: "Following", foreign_key: "stalked_id"
  has_many :followers, through: :opposite_followings, source: :follower
  
  def follow(user)
    stalked_users << user
  end
  
  def stop_followin!
    stalked_users.clear
  end
  
  def so_lonely?
  end
end


class Following < ActiveRecord::Base
  belongs_to :follower, class_name: "User"
  belongs_to :stalked, class_name: "User"
end