Question
Which of the following statements accurately describes
the characteristics of a primary key in a relational database?Solution
A primary key is a critical concept in relational databases, ensuring that each record within a table can be uniquely identified. The primary key has the following key characteristics: • Uniqueness: Each value of a primary key must be unique across the entire table. No two rows can have the same primary key value. • Non-nullable: A primary key must always have a value; it cannot be null. This is essential for maintaining the integrity of the database as it ensures that every record can be uniquely identified.
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