Databricks Certified Data Engineer Professional — Question 96
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; the target table is materialized by directly querying all valid files in the source directory.
- 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.
- E. 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.
Correct answer: D
Explanation
The correct answer, D, accurately describes how Databricks Auto Loader identifies new files by listing the input directory and ensures that they are loaded incrementally and idempotently into the target Delta Lake table. Other options either describe incorrect methods of file detection or do not accurately reflect Auto Loader's default behavior, such as relying on webhooks or cloud vendor-specific services.