In SQL, what is the purpose of modifying existing data?

Modifying existing data in SQL primarily serves to update incorrect or outdated information within a database. This can involve changing values in a record to ensure they reflect the most current and accurate state of the information. For instance, if there is an employee record with an outdated address or a product entry with an incorrect price, the UPDATE statement in SQL allows you to specify which data should change and what the new values should be.

Keeping data current is crucial for maintaining the integrity and reliability of the database, as it ensures that users and applications relying on this data will have access to the most relevant information. In contrast, adding new records pertains to inserting data into a database, creating backups involves making copies for data recovery purposes, and deleting old records is about removing data rather than modifying it. This distinct focus on correcting data makes updating inaccurate or obsolete information the primary purpose when modifying existing entries.