Chapter 2, Problem 2.15RQ

Explanation of Solution

Surrogate primary key:

• A system assigned primary key in a relational database such as a serial number or any other which is not derived from any data in the database is known as surrogate primary key.
• It is deputy of the primary key and will act as a primary key in the database and does not have any other significance.
• To simplify the primary key structures in the database, surrogate primary keys are created, and this ensures unique identification process in a relation.

Conditions to use the surrogate key:

The surrogate key for a relation is created when a primary key of a relation holds the below three conditions:

• If the relation has a composite primary key, then surrogate key should be created...