Fill missing uuid on the application_settings table

db/migrate/20170426175636_fill_missing_uuid_on_application_settings.rb

+class FillMissingUuidOnApplicationSettings < ActiveRecord::Migration
+  DOWNTIME = false
+
+  def up
+    execute("UPDATE application_settings SET uuid = #{quote(SecureRandom.uuid)} WHERE uuid is NULL")
+  end
+
+  def down
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170424142900) do
+ActiveRecord::Schema.define(version: 20170426175636) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"