media_type not nil

db/migrate/20140328144310_add_youtube_to_media_type.rb

@@ -0,0 +1,8 @@
+class AddYoutubeToMediaType < ActiveRecord::Migration
+  def up    
+    Event.where(:media_type => nil).each do |e|
+      e.media_type = "YouTube"
+      e.save(:validate => false)
+    end
+  end
+end