Question 250
A customer data platform ingests evolving JSON and CSV partner payloads. A reviewer sees that engineers chose Restore the persisted Auto Loader schema directory from backup or safely rebootstrap. To verify An existing schema location was deleted and streaming now cannot reliably recover its previous schema, what should the reviewer observe?
Explanation
Correct Answer
The acceptance criterion for “An existing schema location was deleted and streaming now cannot reliably recover its previous schema” is The stream resumes with the expected column definitions and history state; this is the expected evidence after Restore the persisted Auto Loader schema directory from backup or safely rebootstrap.
Incorrect Answers
The stream detects a new column, updates schema metadata and resumes after restart would demonstrate the separate action Configure Auto Loader `addNewColumns` and a persistent schemaLocation, which addresses “New JSON attributes should become accepted target columns after a managed restart.” It does not verify the requirement “An existing schema location was deleted and streaming now cannot reliably recover its previous schema” following Restore the persisted Auto Loader schema directory from backup or safely rebootstrap.
The target schema includes the approved field with existing rows preserved pertains to a different control (Allow the supported schema evolution update and restart as required) and a different need (An optional field appears for the first time and is approved for schema evolution). It cannot establish that Restore the persisted Auto Loader schema directory from backup or safely rebootstrap met the stated goal.
This signal belongs to the adjacent case “A foreign schema evolves and analysts cannot see a new remote column,” whose remedy is Refresh the supported foreign catalog metadata or mappings. The observed result for the present requirement is The stream resumes with the expected column definitions and history state.