Databricks Data Engineer Associate Question 305
Select 2In Databricks, which kinds of files does the OPTIMIZE command compact when used on a Delta table?
- A
Small files to create fewer larger files
- B
Corrupted files that fail to load into the Delta table
- C
Large files to split them into smaller files
- D
Files within a Delta table that belong to the same partition
Show answer and explanation
Correct answers: A, D
Explanation
The OPTIMIZE command in Databricks is primarily used to compact small files within a Delta table into larger files, which minimizes the overhead of managing a large number of small files and improves query performance. Additionally, OPTIMIZE operates within the same partition of a Delta table to ensure data locality and efficient storage organization. It does not handle corrupted files or split large files into smaller ones.
- A. Correct.
Correct: OPTIMIZE is used to compact small files into larger files, improving query performance by reducing the number of files read during execution.
- B. Incorrect.
Incorrect: OPTIMIZE does not repair or handle corrupted files. Such files need to be addressed separately through data repair or cleaning processes.
- C. Incorrect.
Incorrect: OPTIMIZE does not split large files into smaller ones. Instead, its purpose is to consolidate small files into fewer, larger files.
- D. Correct.
Correct: OPTIMIZE works on files within the same partition of a Delta table to compact them, ensuring efficient data organization and retrieval.