In terms of database management, what is an index primarily used for?

An index in database management is primarily used to facilitate faster searches in the database. It acts like a reference point, similar to an index at the back of a book, which allows the database management system to quickly locate and retrieve the relevant data without having to scan every record in a table. This significantly improves the performance of queries, especially on large datasets, as indexes enable quick lookups and reduce the time it takes to fetch results.

Indexes work by creating a data structure that holds pointers to the actual data records, allowing for efficient searching based on specific columns or attributes. This is particularly useful for operations involving filtering and sorting data, which can consume a lot of time if done without an index.

While the other options mention aspects of database operations, they do not reflect the primary function of an index. For instance, increasing the complexity of data relationships does not pertain to indexing; data integrity checks relate more to ensuring data is accurate and consistent, and converting databases to different formats focuses on data transformation rather than data retrieval efficiency.