Why would a database be denormalized?

A.
To ensure data integrity

B.
To increase processing efficiency

C.
To prevent duplication of data

D.
To save storage space

Explanation:
The purpose of denormalization is to improve the read performance and processing efficiency of a database by
adding redundant data or by grouping data.
Incorrect Answers:
A: The duplication of data creates a problem for data integrity as the data needs to be updated in numerous
places. Normalization, which eliminates the duplication of data, improves data integrity.
C: The purpose of normalization is to eliminate duplication of the data. All duplicated data items should be
deleted and replaced by a pointer. Denormalization could reverse this process. It attempts to improve the read
performance and processing efficiency of a database by adding redundant data or by grouping data.
D: The purpose of denormalization is to improve the read performance and processing efficiency of a database
by adding redundant data or by grouping data. This increases storage space consumption.

https://en.wikipedia.org/wiki/Denormalization
https://en.wikipedia.org/wiki/Database_normalization
Miller, David R., CISSP Training Kit, O’Reilly Media, Sebastopol, 2013, pp. 620, 622