-class AddUniqueNameIndexToLinks < ActiveRecord::Migration
+# Copyright (C) The Arvados Authors. All rights reserved.
+#
+# SPDX-License-Identifier: AGPL-3.0
+
+class AddUniqueNameIndexToLinks < ActiveRecord::Migration[4.2]
def change
# Make sure PgPower is here. Otherwise the "where" will be ignored
# and we'll end up with a far too restrictive unique