Databricks Certified Data Engineer Professional — Question 170

Which statement describes the default execution mode for Databricks Auto Loader?

Answer options

• A. Cloud vendor-specific queue storage and notification services are configured to track newly arriving files; new files are incrementally and idempotently loaded into the target Delta Lake table.
• B. New files are identified by listing the input directory; the target table is materialized by directly querying all valid files in the source directory.
• C. Webhooks trigger a Databricks job to run anytime new data arrives in a source directory; new data are automatically merged into target tables using rules inferred from the data.
• D. New files are identified by listing the input directory; new files are incrementally and idempotently loaded into the target Delta Lake table.

Correct answer: D

Explanation

The correct answer, D, accurately describes how Databricks Auto Loader identifies new files by listing the input directory and loading them into the Delta Lake table incrementally and idempotently. Option A discusses queue storage and notification services, which is not the default mode. Option B mentions materializing the target table by querying all valid files, which is not how Auto Loader operates. Option C incorrectly describes the use of webhooks, which is not part of the default execution mode of Auto Loader.