What does referential integrity in databases ensure?

Referential integrity is a fundamental principle in database design that ensures the relationships between tables remain consistent. It specifically enforces rules that maintain the accuracy and consistency of data across related tables. For example, when a foreign key attribute in one table refers to a primary key in another table, referential integrity prevents actions that would leave orphaned records. This means that every foreign key value must correspond to an existing primary key value, thus preserving the validity of the relationships set up within the database.

This characteristic of referential integrity is essential for maintaining the logical connections that define the relationships between different entities in a database. When referential integrity is enforced, it prevents scenarios where data might reference non-existent entries, ensuring that the integrity of the database structure is upheld over time.

The other options, while they relate to database management concepts, do not define referential integrity specifically. Data redundancy being minimized pertains more to normalization practices, efficient data storage relates to database architecture and design principles, and access control is a matter of security management rather than the consistency of data relationships.