Introduce a SelectedTalk model

app/models/application_record.rb

@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end

app/models/selected_talk.rb

@@ -0,0 +1,7 @@
+class SelectedTalk < ApplicationRecord
+  belongs_to :talk_preference
+
+  def talk
+    Talk.find talk_id, from: :halfnarp_friendly
+  end
+end

app/models/talk.rb

@@ -1,4 +1,6 @@
 class Talk < ActiveResource::Base
+  has_many :selections, class_name: 'SelectedTalk'
+
   self.site = "https://cfp.openfest.org/api/conferences/3"
   self.element_name = "event"
 

app/models/talk_preference.rb

@@ -1,4 +1,6 @@
 class TalkPreference < ActiveRecord::Base
+  has_many :selected_talks
+
   self.primary_key = :unique_id
 
   serialize :talks, Array

db/migrate/20161005112915_create_selected_talks.rb

@@ -0,0 +1,28 @@
+class TalkPreference < ActiveRecord::Base
+  self.primary_key = :unique_id
+  serialize :talks, Array
+end
+
+class SelectedTalk < ApplicationRecord
+end
+
+class CreateSelectedTalks < ActiveRecord::Migration[5.0]
+  def up
+    create_table :selected_talks do |t|
+      t.references :talk, foreign_key: false
+      t.string :talk_preference_id, foreign_key: true
+    end
+
+    talk_preferences = TalkPreference.all
+
+    talk_preferences.each do |preference|
+      preference.talks.each do |talk|
+        SelectedTalk.create! talk_id: talk, talk_preference_id: preference.unique_id
+      end
+    end
+  end
+
+  def down
+    drop_table :selected_talks
+  end
+end