text: -- Licensed to the Apache Software Foundation (ASF) under one or more
  -- contributor license agreements.  See the NOTICE file distributed with
  -- this work for additional information regarding copyright ownership.
  -- The ASF licenses this file to You under the Apache License, Version 2.0
  -- (the "License"); you may not use this file except in compliance with
  -- the License.  You may obtain a copy of the License at
  --
  --     http://www.apache.org/licenses/LICENSE-2.0
  --
  -- Unless required by applicable law or agreed to in writing, software
  -- distributed under the License is distributed on an "AS IS" BASIS,
  -- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  -- See the License for the specific language governing permissions and
  -- limitations under the License.
  BEGIN
  	IF EXISTS(select * from SYS.SYSCOLUMNS where tname = 'x_policy' and cname in('guid','service','zone_id') THEN
  		IF NOT EXISTS(select * from SYS.SYSCONSTRAINT where constraint_name = 'x_policy_UK_guid_service_zone') THEN
  			ALTER TABLE dbo.x_policy ADD CONSTRAINT x_policy_UK_guid_service_zone UNIQUE NONCLUSTERED (guid,service,zone_id);
  		END IF;
  	END IF;
  END
  GO