Config option sqlite_db is deprecated in 0a1bae9859079fb21a03716be947c5f1da6db0a2, and deprecate argumentsqlite_db in method set_defaults in https://review.openstack.org/#/c/350945/, should use config option connection instead. For watcher, we test database with sqlite in memory mode [1] as below: cfg.CONF.set_override("connection", "sqlite://", group="database", enforce_type=True) and don't use config option sqlite_db, so remove unused code. [1]http://docs.sqlalchemy.org/en/rel_1_0/core/engines.html#sqlite Change-Id: I9b1f995e1b7004bcfe6c5a854c2f83b24e5bfb56