Databricks Data Engineer Professional Question 19
Single answerA data engineering team wants to create a clone of an existing Delta table to use for testing purposes. They would like to ensure that the cloned table is independent of the original and does not share storage. Which type of Delta clone should they create, and what is the correct syntax?
- A
Create a shallow clone using 'CREATE TABLE new_table SHALLOW CLONE source_table'
- B
Create a deep clone using 'CREATE TABLE new_table DEEP CLONE source_table'
- C
Create a deep clone using 'CLONE TABLE source_table AS new_table'
- D
Create a shallow clone using 'CLONE TABLE source_table INTO new_table'
Show answer and explanation
Correct answer: B
Explanation
Delta clones in Databricks allow for creating copies of Delta tables. A shallow clone shares storage with the source table and is faster to create, whereas a deep clone creates a fully independent copy of the table. The correct syntax for creating a deep clone is 'CREATE TABLE new_table DEEP CLONE source_table'. This ensures the cloned table is independent of the original, which meets the team's requirement for testing purposes.
- A. Incorrect.
This syntax is incorrect for creating a shallow clone. While shallow clones are faster and share storage, the given syntax is not valid for Delta clones.
- B. Correct.
This is the correct answer. A deep clone creates a full copy of the original Delta table, making it independent of the source table. The syntax 'CREATE TABLE new_table DEEP CLONE source_table' is valid and appropriate.
- C. Incorrect.
This syntax is invalid for creating Delta clones. Delta clones require specific keywords like 'SHALLOW CLONE' or 'DEEP CLONE' in the 'CREATE TABLE' statement.
- D. Incorrect.
This syntax is also invalid for Delta clones, as it does not match the required format for creating a clone using the Delta Lake framework.