'Given a list of known DAGs, deactivate any other DAGs that are
marked as active in the ORM
:param active_dag_ids: list of DAG IDs that are active
:type active_dag_ids: list[unicode]
:return: None'

@staticmethod
@provide_session
def deactivate_unknown_dags(active_dag_ids, session=None):

    if (len(active_dag_ids) == 0):
        return
    for dag in session.query(DagModel).filter((~ DagModel.dag_id.in_(active_dag_ids))).all():
        dag.is_active = False
        session.merge(dag)
