Data Processing Data Quality and Validation 2

Question 1

What is referential integrity in a relational database?

Accepted Answer

Ensuring foreign key values always reference existing primary key values

Answer

Referential integrity ensures that foreign key values in one table always match existing primary key values in the referenced table.

Question 2

What is the purpose of a checksum in data validation?

Accepted Answer

To detect errors or corruption in transmitted or stored data

Answer

A checksum is a computed value derived from data that is compared after transmission or storage to detect any corruption or tampering.

Question 3

What is data consistency in data processing?

Accepted Answer

Data is the same across all systems and does not contradict itself

Answer

Data consistency means the same data entity shows the same values across all systems and datasets, with no conflicting information.

Question 4

Which process automatically corrects or standardizes data to meet quality standards?

Accepted Answer

Data cleansing

Answer

Data cleansing identifies and corrects errors, inconsistencies, and formatting issues to improve overall data quality.

Question 5

What is a null value in a database?

Accepted Answer

The absence of any value — unknown or missing data

Answer

NULL represents the absence of a value in a field — it is different from zero or an empty string and means the data is unknown or missing.

Data Processing Practice Test