nova/nova/db/sqlalchemy/migrate_repo/versions/347_add_updated_at_index.py

57 lines
2.0 KiB
Python

# 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 oslo_log import log as logging
from sqlalchemy import MetaData, Table, Index
from sqlalchemy.engine import reflection
LOG = logging.getLogger(__name__)
INDEX_COLUMNS_1 = ['project_id']
INDEX_NAME_1 = 'instances_project_id_idx'
INDEX_COLUMNS_2 = ['updated_at', 'project_id']
INDEX_NAME_2 = 'instances_updated_at_project_id_idx'
TABLE_NAME = 'instances'
def _get_table_index(migrate_engine, table_name, index_columns):
inspector = reflection.Inspector.from_engine(migrate_engine)
for idx in inspector.get_indexes(table_name):
if idx['column_names'] == index_columns:
break
else:
idx = None
return idx
def upgrade(migrate_engine):
meta = MetaData()
meta.bind = migrate_engine
table = Table(TABLE_NAME, meta, autoload=True)
if _get_table_index(migrate_engine, TABLE_NAME, INDEX_COLUMNS_1):
LOG.info('Skipped adding %s because an equivalent index'
' already exists.', INDEX_NAME_1)
else:
columns = [getattr(table.c, col_name) for col_name in INDEX_COLUMNS_1]
index = Index(INDEX_NAME_1, *columns)
index.create(migrate_engine)
if _get_table_index(migrate_engine, TABLE_NAME, INDEX_COLUMNS_2):
LOG.info('Skipped adding %s because an equivalent index'
' already exists.', INDEX_NAME_2)
else:
columns = [getattr(table.c, col_name) for col_name in INDEX_COLUMNS_2]
index = Index(INDEX_NAME_2, *columns)
index.create(migrate_engine)