One important constraint in a relational database environment is that a primary key uniquely identifies each row in a data table.This principle is called the
A)entity integrity rule.
B)referential integrity rule.
C)unique primary key rule.
D)foreign key rule.

Question

Quizplus · Accepted Answer

The primary key is used to enforce the entity integrity rule, which requires that each row in a table be unique and identifiable. This means that each row must have a unique primary key. The referential integrity rule applies to relationships between tables and ensures that a foreign key in one table refers to a valid primary key in another table. However, this is not the main constraint related to primary keys. While the unique primary key rule is important, it does not capture the full requirement of uniquely identifying each row in a table. Therefore, choice C is not the best answer. The foreign key rule is also important but is not directly related to the primary key constraint. Therefore, choice D is not the best answer either.

One Important Constraint in a Relational Database Environment Is That