class CreateActivities < ActiveRecord::Migration
  def self.up
    create_table :activities do |t|
      t.string   :activity_type, :subject_type,  :actor_type,  :secondary_subject_type
      t.integer               :subject_id,    :actor_id,    :secondary_subject_id
      t.timestamps
    end
  end
 
  def self.down
    drop_table :activities
  end
end