Debugging airflow tasks using airflow test vs using DebugExecutor

What is the main difference between these two?

Debug Executor runs a full DAG Run so you can test the trigger rules. airflow test command run only one task.

This is even clearer in Airflow 2.0. We have separate commands:

• airflow dags test - starts one DAG Run with DebugExecutor.
• airflow tasks test - starts one tasks.

Does airflow test uses DebugExecutor under the hood?

No. If you use DebugExecutor then you need to run full scheduler. If you use the airflow task command, only code that is being executed by worker is executed.

Is there a way to run/debug dags and tasks without running Airflow database and creating dependent pools and queues?

You can load a DAG with DagBag and then call the execute method of your task.

from airflow.model.dagbag import DagBag
dag_file_path = "/home/test-user/dags/dag-file.py"
dagbag = DagBag(dag_folder=dag_file_path)
dagbag.dags['test-dag-id'].task_dict['task-id'].execute({})