Databricks Data Engineer Professional Question 8
Select 3You are designing a data pipeline using Delta Lake on Databricks to process financial transaction data. The pipeline is expected to handle frequent updates and deletes while ensuring data reliability. How does Delta Lake leverage the transaction log and cloud object storage to guarantee atomicity and durability?
- A
Delta Lake uses the transaction log to record all changes to the data, enabling atomic commits.
- B
Delta Lake stores multiple copies of the data in the cloud object storage to ensure durability.
- C
The transaction log keeps a record of the data's state at each version, allowing operations to be rolled back if needed.
- D
Delta Lake relies solely on cloud object storage to guarantee atomicity and durability.
- E
Cloud object storage ensures durability by persisting data independently of the compute layer.
Show answer and explanation
Correct answers: A, C, E
Explanation
Delta Lake guarantees atomicity and durability by leveraging the transaction log and cloud object storage together. The transaction log ensures atomic changes by recording every operation and maintaining a versioned history for rollback capabilities. Cloud object storage ensures durability by persisting data reliably across distributed storage systems. Together, these components provide strong guarantees for data reliability and consistency in Delta Lake.
- A. Correct.
Correct. The transaction log in Delta Lake tracks every change to the data, ensuring atomicity by applying changes as a single, indivisible operation.
- B. Incorrect.
Incorrect. Delta Lake does not store multiple copies of the data itself; instead, it relies on the transaction log and cloud object storage for durability and consistency.
- C. Correct.
Correct. The transaction log provides a versioned history of the data, enabling rollback and ensuring operations are atomic even in case of failures.
- D. Incorrect.
Incorrect. Delta Lake combines the use of the transaction log and cloud object storage to guarantee both atomicity and durability. It does not rely on cloud object storage alone.
- E. Correct.
Correct. Cloud object storage guarantees durability by persisting data across multiple physical locations, ensuring it is safe from hardware failures.