In a relational database, what does a foreign key do?

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Question: In a relational database, what does a foreign key do?

Options:

Correct Answer: All of the above

Solution:

A foreign key links two tables together, ensures data integrity, and can act as a primary key in another table.

In a relational database, what does a foreign key do?

In a relational database, what does a foreign key do?

Step 1: Understand that a relational database is made up of tables that store data.
Step 2: Know that a foreign key is a special column in one table that refers to the primary key of another table.
Step 3: Realize that the foreign key creates a link between the two tables, allowing them to relate to each other.
Step 4: Learn that this link helps maintain data integrity, meaning it ensures that the data is accurate and consistent across both tables.
Step 5: Remember that a foreign key can also be a primary key in the table where it is located, meaning it can uniquely identify records in that table.

Foreign Key – A foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another table, establishing a relationship between the two tables.
Data Integrity – Foreign keys help maintain data integrity by ensuring that relationships between tables remain consistent.
Primary Key Relationship – A foreign key can reference a primary key in another table, allowing for the establishment of relationships between different entities.