Astronomer Apache Airflow 3 Fundamentals · 20% practice allocation
5 free sample questions from the Operators, Tasks, and Dependencies domain, with answers and explanations. The full Apache Airflow 3 Fundamentals bank has 55 questions across 4 domains. Questions are scenario-based and written from the official Astronomer exam guide.
Which operator runs a shell command as a task?
The BashOperator executes a Bash/shell command. The PythonOperator (A) runs Python callables, SqlSensor (B) waits for a SQL condition, and EmptyOperator (D) is a no-op placeholder.
A cleanup task must run whether the upstream tasks succeeded or failed (as long as they've all finished). Which trigger rule should it use?
all_done fires once all upstream tasks have completed regardless of their success or failure — ideal for cleanup/teardown tasks. all_success (B) requires all to succeed, one_success (A) needs at least one success, and none_failed (D) requires no failures (skipped is allowed).
Which operator is a no-op placeholder often used to group tasks or mark start/end points in a DAG?
The EmptyOperator (previously DummyOperator) does nothing and is used to structure a DAG — grouping branches or marking start/join/end points. The PythonOperator (D) and BashOperator (B) do real work, and S3KeySensor (A) waits for an S3 object.
Which operator would you use to execute an arbitrary Python function as a task?
The PythonOperator runs a Python callable (function) as a task. The BashOperator (B) runs shell commands, the EmailOperator (C) sends email, and the DummyOperator/EmptyOperator (D) does nothing (a placeholder).
Why should XComs NOT be used to pass large datasets between tasks?
XCom values are stored in the metadata database, so they're intended for small data; passing large datasets would bloat the database and degrade performance — pass a reference (e.g., an S3 path) instead. XComs aren't limited to integers (C), and options A and D are inaccurate.
The free Apache Airflow 3 Fundamentals practice test mixes about 20 questions weighted like the exam. The full 55-question bank adds instant grading, flashcards and a timed mock exam.