@property
    def connection(self):
        return self._clone(connection=True)
If the update depends on results from other tables, we need to do some
dataset/ETHPy150Open openstack/oslo.db/oslo_db/sqlalchemy/enginefacade.py/_TransactionContextManager.connection--crossover with--dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/Django-1.6.10/django/db/models/sql/compiler.py/SQLUpdateCompiler.pre_sql_setup