Which of the following is NOT a feature of a Foreign Key?

The characteristic that makes a foreign key distinct is that it does not uniquely identify a record; rather, it serves to establish a connection between two tables. A foreign key is used within a database to create a relationship between the data in different tables, which is essential for maintaining data integrity and enforcing referential integrity.

Let’s clarify the roles of the other features:

• Establishing relationships between tables is a critical function of a foreign key. It points to a primary key in another table, allowing for meaningful connections and data retrieval across different datasets.

• A foreign key can refer to a primary key in another table, solidifying that connection and enabling more complex queries and operations where data in one table relates to data in another.

• Importantly, foreign keys can have duplicate values. This is a fundamental aspect of their purpose in relational database design, as multiple records in one table may relate to the same record in another table.

Thus, the nature of a foreign key is to create relationships and allow for duplicates, rather than to uniquely identify a record, which is the role of a primary key. This understanding reinforces the concept of how relational databases are structured and how data is interconnected.