def rollback_unlock_tables(session):
"""Rollback and unlock tables
supported backends: MySQL and PostgreSQL
"""
session.rollback()
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
def commit_unlock_tables(session):
"""Commit and unlock tables for supported backends: MySQL and PostgreSQL"""
session.commit()
session.execute('COMMIT') # execute COMMIT on DB backend
# because sqlalchemy session does not guarantee
# exact boundary correspondence to DB backend transactions
# We must guarantee DB commits transaction before UNLOCK
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
def rollback_unlock_tables(session):
"""Rollback and unlock tables
supported backends: MySQL and PostgreSQL
"""
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
# postgres automatically releases lock at transaction end
session.rollback()
def rollback_unlock_tables(session):
"""Rollback and unlock tables
supported backends: MySQL and PostgreSQL
"""
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
# postgres automatically releases lock at transaction end
session.rollback()
def commit_unlock_tables(session):
"""Commit and unlock tables for supported backends: MySQL and PostgreSQL"""
try:
session.execute('COMMIT') # execute COMMIT on DB backend
session.commit()
# because sqlalchemy session does not guarantee
# exact boundary correspondence to DB backend transactions
# We must guarantee DB commits transaction before UNLOCK
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
# postgres automatically releases lock at transaction end
except db_exc.DBDataError as exc:
LOG.exception('Database backend experienced data error.')
raise congress_exc.DatabaseDataError(data=exc)
def commit_unlock_tables(session):
"""Commit and unlock tables for supported backends: MySQL and PostgreSQL"""
try:
session.execute('COMMIT') # execute COMMIT on DB backend
session.commit()
# because sqlalchemy session does not guarantee
# exact boundary correspondence to DB backend transactions
# We must guarantee DB commits transaction before UNLOCK
# unlock
if is_mysql():
session.execute('UNLOCK TABLES')
# postgres automatically releases lock at transaction end
except db_exc.DBDataError as exc:
LOG.exception('Database backend experienced data error.')
raise congress_exc.DatabaseDataError(data=exc)
def lock_tables(session, tables):
"""Write-lock tables for supported backends: MySQL and PostgreSQL"""
session.begin(subtransactions=True)
if is_mysql(): # Explicitly LOCK TABLES for MySQL
session.execute('SET autocommit=0')
session.execute('LOCK TABLES {}'.format(
','.join([table + ' WRITE' for table in tables])))
elif is_postgres(): # Explicitly LOCK TABLE for Postgres
session.execute('BEGIN TRANSACTION')
for table in tables:
session.execute('LOCK TABLE {} IN EXCLUSIVE MODE'.format(table))
def lock_tables(session, tables):
"""Write-lock tables for supported backends: MySQL and PostgreSQL"""
session.begin(subtransactions=True)
if is_mysql(): # Explicitly LOCK TABLES for MySQL
session.execute('SET autocommit=0')
session.execute('LOCK TABLES {}'.format(
','.join([table + ' WRITE' for table in tables])))
elif is_postgres(): # Explicitly LOCK TABLE for Postgres
session.execute('BEGIN TRANSACTION')
for table in tables:
session.execute('LOCK TABLE {} IN EXCLUSIVE MODE'.format(table))
