A Level Computer Science OCR Practice Exam 2026 - Free Practice Questions and Study Guide

Indexing significantly enhances the performance of data retrieval operations within a database. When a database has an index, it can quickly locate the position of the data on the storage medium rather than scanning the entire dataset. This is similar to how an index in a book allows you to find information rapidly without having to read every page. By using various data structures such as B-trees or hash tables, indexing reduces the number of disk I/O operations required to access specific records, leading to faster query response times.

The other options, while possibly related to database management, do not accurately describe the primary function of indexing. For instance, while indexing may aid in efficient data access, it does not inherently reduce the overall size of the database nor does it simplify the relationships between tables—those concerns are managed through database normalization and design strategies. Similarly, indexing does not combine multiple records into one; it instead allows for quicker access to existing records without altering their structure.