In regard to atomicity, what happens if an error occurs during a transaction?

Atomicity, a fundamental principle of database transactions, ensures that a transaction is treated as a single, indivisible unit. This means that either all components of the transaction are successfully completed, or none of them are applied at all.

When an error occurs during a transaction, atomicity dictates that any changes that have been made prior to the error must be rolled back or "backed out." This rollback ensures that the database retains its integrity and consistency. Therefore, the changes made during the transaction are undone, returning the database to the state it was in before the transaction began.

This aspect of atomicity is crucial for maintaining the reliability of data in a database system. If only the completed parts of the transaction were saved or if the transaction continued uninterrupted, it could result in data inconsistencies and corruption. Implementing a rollback in case of an error prevents these issues, thereby upholding the overall integrity of the systems involved.