text: # Copyright 2011 OpenStack Foundation
  # All Rights Reserved.
  #
  #    Licensed 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.
  
  from sqlalchemy import *  # noqa
  
  from glance.db.sqlalchemy.migrate_repo.schema import from_migration_import
  
  
  def get_images_table(meta):
      """
      No changes to the image properties table from 002...
      """
      (get_images_table,) = from_migration_import(
          '004_add_checksum', ['get_images_table'])
  
      images = get_images_table(meta)
      return images
  
  
  def upgrade(migrate_engine):
      meta = MetaData()
      meta.bind = migrate_engine
  
      (get_image_properties_table,) = from_migration_import(
          '004_add_checksum', ['get_image_properties_table'])
      image_properties = get_image_properties_table(meta)
  
      if migrate_engine.name == "ibm_db_sa":
          # NOTE(dperaza) ibm db2 does not allow ALTER INDEX so we will drop
          # the index, rename the column, then re-create the index
          sql_commands = [
              """ALTER TABLE image_properties DROP UNIQUE
                  ix_image_properties_image_id_key;""",
              """ALTER TABLE image_properties RENAME COLUMN \"key\" to name;""",
              """ALTER TABLE image_properties ADD CONSTRAINT
                  ix_image_properties_image_id_name UNIQUE(image_id, name);""",
          ]
          for command in sql_commands:
              meta.bind.execute(command)
      else:
          index = Index('ix_image_properties_image_id_key',
                        image_properties.c.image_id,
                        image_properties.c.key)
          index.rename('ix_image_properties_image_id_name')
  
          image_properties = get_image_properties_table(meta)
          image_properties.columns['key'].alter(name="name")
  