In a relational database, how is a primary key utilized in a one-to-one relationship?

In a relational database, how is a primary key utilized in a one-to-one relationship?

• A. It uniquely identifies a record in only its own table.
• B. It can also be a foreign key in another table.
• C. It prevents data duplication within the same table.
• D. It allows for many records in another table.

Answer: (B)

In a one-to-one relationship within a relational database, the primary key from one table is essential in identifying a unique record and can also serve as a foreign key in another table. This structure reinforces the relationship between the two tables, ensuring that each record in the first table corresponds to a single, unique record in the second table. Utilizing a primary key as a foreign key means that it brings the integrity of the data across the two tables, enabling them to maintain a strict one-to-one correspondence. This design is crucial for maintaining data consistency and integrity, as it allows the two tables to effectively link to each other. In contrast, a primary key’s role in uniquely identifying a record pertains to its specific table rather than across relationships. Preventing data duplication focuses on the functionality of the primary key within the same table, which does not illustrate the nature of the one-to-one relationship. Furthermore, the allowance for many records in another table describes a different type of relationship, specifically a one-to-many relationship, rather than the one-to-one nature that is being analyzed in this context.

In a one-to-one relationship within a relational database, the primary key from one table is essential in identifying a unique record and can also serve as a foreign key in another table. This structure reinforces the relationship between the two tables, ensuring that each record in the first table corresponds to a single, unique record in the second table.

Utilizing a primary key as a foreign key means that it brings the integrity of the data across the two tables, enabling them to maintain a strict one-to-one correspondence. This design is crucial for maintaining data consistency and integrity, as it allows the two tables to effectively link to each other.

In contrast, a primary key’s role in uniquely identifying a record pertains to its specific table rather than across relationships. Preventing data duplication focuses on the functionality of the primary key within the same table, which does not illustrate the nature of the one-to-one relationship. Furthermore, the allowance for many records in another table describes a different type of relationship, specifically a one-to-many relationship, rather than the one-to-one nature that is being analyzed in this context.