"""
        Tests if fractional seconds are stored in the database
        """
        dag_id = "test_fractional_seconds"
        dag = DAG(dag_id=dag_id, schedule="@once")
        dag.add_task(BaseOperator(task_id="faketastic", owner="Also fake", start_date=TEST_DATE))
        start_date = timezone.utcnow()
        run = dag.create_dagrun(
            run_id="test_" + start_date.isoformat(),
            execution_date=start_date,
            start_date=start_date,
            state=State.RUNNING,
            external_trigger=False,
        )
        run.refresh_from_db()
        assert start_date == run.execution_date, "dag run execution_date loses precision"
        assert start_date == run.start_date, "dag run start_date loses precision "
        self._clean_up(dag_id)
    def test_pickling(self):
        test_dag_id = "test_pickling"
        args = {"owner": "airflow", "start_date": DEFAULT_DATE}
        dag = DAG(test_dag_id, default_args=args)
        dag_pickle = dag.pickle()
        assert dag_pickle.pickle.dag_id == dag.dag_id
    def test_rich_comparison_ops(self):
        test_dag_id = "test_rich_comparison_ops"
        class DAGsubclass(DAG):