Do indexes always speed up the work of a relational database?

Indexes in relational databases usually speed up search and data retrieval operations because they allow the DBMS to quickly find the needed records without scanning the entire table. However, indexes do not always improve performance:

• During frequent insert, update, or delete operations, indexes require additional time to maintain their structure, which can slow down these operations.
• If queries do not use the fields on which indexes are created, they will not provide any acceleration.
• An excessive number of indexes increases memory usage and can negatively impact performance.

Therefore, indexes should be created consciously, analyzing the types of queries and the load on the database.