Databricks Data Engineer Associate Question 344
Select 3A data engineering team is tasked with updating a Delta table that tracks customer transactions. The table should handle new records, updates to existing records, and deletions efficiently without overwriting the entire dataset. Which of the following benefits of the MERGE command make it suitable for this task?
- A
It allows conditional logic to handle inserts, updates, and deletes in a single operation.
- B
It automatically compacts small files created during frequent writes to the Delta table.
- C
It ensures ACID compliance for all operations, maintaining data integrity in concurrent environments.
- D
It avoids the need to write custom logic for merging datasets, simplifying implementation.
- E
It provides automatic schema evolution for the Delta table.
Show answer and explanation
Correct answers: A, C, D
Explanation
The MERGE command is a powerful feature of Delta Lake that supports conditional logic for inserts, updates, and deletes, ensuring ACID compliance and simplifying implementation. This makes it suitable for tasks that involve modifying Delta tables without overwriting the entire dataset. However, features like file compaction and schema evolution, while part of Delta Lake, are not directly tied to the MERGE command.
- A. Correct.
Correct: The MERGE command supports conditional logic to handle different actions (e.g., inserts, updates, deletes) based on specified conditions, making it efficient for tasks like updating Delta tables.
- B. Incorrect.
Incorrect: The MERGE command itself does not compact small files. File compaction is achieved through Delta Lake optimization features like
OPTIMIZE. - C. Correct.
Correct: The MERGE command ensures ACID compliance, which is essential for maintaining data integrity when handling concurrent operations on Delta tables.
- D. Correct.
Correct: The MERGE command simplifies implementation by eliminating the need for custom logic to merge datasets.
- E. Incorrect.
Incorrect: While Delta Lake supports schema evolution, this feature is not a direct benefit of the MERGE command.