So, what are some scenarios where Airflow XCom exclusive communication is particularly useful?
: If your data payload is larger than 10 Kilobytes, it does not belong in the standard Airflow database. Use a custom backend or write it to a data lake directly.
When a task returns a value, Airflow passes it through your custom backend class. The backend:
Push only once, never overwrite a key. Use execution_date + task_id as part of the key. Enable exclusive mode to prevent accidental re-push.
: Tasks "push" data by returning a value from an operator's execute() method or by explicitly calling task_instance.xcom_push() .
For enterprise data pipelines, storing data in the metadata database is a significant anti-pattern. Airflow provides an exclusive feature to override this behavior: .
