What is the principle of atomicity of a transaction in a database?

The principle of atomicity of a transaction in a database means that the transaction is considered an indivisible unit of work: either all operations within the transaction are successfully completed, or none of them are applied. This guarantees data integrity.

If an error occurs during the execution of a transaction, all changes are rolled back, and the database is restored to its state before the transaction began. This prevents partial application of changes that could lead to data inconsistency.