text: # vim: tabstop=4 shiftwidth=4 softtabstop=4
  
  # Copyright (c) 2013 Boris Pavlovic (boris@pavlovic.me).
  # 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 migrate.changeset import UniqueConstraint
  from sqlalchemy import MetaData, Table
  
  from nova.db.sqlalchemy import utils
  
  
  UC_NAME = 'uniq_instance_type_id_x_project_id_x_deleted'
  UC_COLUMNS = ('instance_type_id', 'project_id', 'deleted')
  
  TABLE_NAME = 'instance_type_projects'
  
  
  def upgrade(migrate_engine):
      meta = MetaData(bind=migrate_engine)
      t = Table(TABLE_NAME, meta, autoload=True)
  
      utils.drop_old_duplicate_entries_from_table(migrate_engine, TABLE_NAME,
                                                  True, *UC_COLUMNS)
      uc = UniqueConstraint(*UC_COLUMNS, table=t, name=UC_NAME)
      uc.create()
  
  
  def downgrade(migrate_engine):
      utils.drop_unique_constraint(migrate_engine, TABLE_NAME, UC_NAME,
                                   *UC_COLUMNS)
  