Databricks Data Engineer Professional Question 22
Single answerA data engineering team wants to create a full copy of a Delta table in a development environment for testing purposes. They also want to ensure that the cloned table includes all the historical versions and metadata of the original Delta table. Which Delta clone option should be used in this scenario?
- A
CREATE OR REPLACE TABLE ... CLONE
- B
CREATE TABLE ... CLONE
- C
CREATE TABLE ... SHALLOW CLONE
- D
CREATE TABLE ... DEEP CLONE
Show answer and explanation
Correct answer: D
Explanation
In this scenario, the requirement is to create a full copy of the Delta table that includes all historical versions and metadata. Only a deep clone fulfills this requirement. A shallow clone would only reference the existing data without copying history or metadata, and the syntax must explicitly specify 'DEEP CLONE' to ensure the full copy.
- A. Incorrect.
This option is incorrect because 'CREATE OR REPLACE ... CLONE' is not a valid Delta clone syntax. Delta clone does not support 'OR REPLACE' in its syntax.
- B. Incorrect.
While 'CREATE TABLE ... CLONE' is a valid syntax, it does not specify the type of clone (shallow or deep). Without explicitly choosing a type, it does not guarantee the inclusion of historical versions and metadata.
- C. Incorrect.
A shallow clone creates a reference to the original Delta table's files and does not include historical versions or metadata. This does not meet the requirements of the scenario.
- D. Correct.
A deep clone creates a complete, independent copy of the Delta table, including all its data, history, and metadata. This satisfies the requirement to include all historical versions and metadata.