What is the purpose of a database index?

A database index is specifically designed to enhance the performance of data retrieval operations within a database. By creating a sorted structure that allows the database management system to quickly locate and access the requested data, the index serves as a critical optimization tool. Instead of scanning the entire dataset, which can become time-consuming, the database can utilize the index to pinpoint the exact location of data entries.

In practice, this means that queries can be executed much faster, especially in large databases where the volume of data makes full table scans inefficient. The act of indexing can significantly improve the response time for read operations, making it a vital aspect of database management for applications needing to query data quickly and efficiently.

The other options do not align with the primary purpose of a database index; encryption pertains to securing data, data backups relate to preserving copies of information, and user access management focuses on controlling who can interact with the database, none of which involve the acceleration of data queries.