Database Systems Practice Test

Recovery is the process that restores the database content after a failure. When something goes wrong, the system uses the recorded history of changes (logs) along with backups to bring the database back to a consistent state. By replaying the log, the database can redo actions from committed transactions and undo those from unfinished ones, ensuring that all data reflects a valid, durable state. This is why recovery is the term that fits best for recovering content after a failure.

The other terms relate to different ideas. A view materialized is about storing the results of a query to speed up access, not about restoring data after a crash. Encryption and a decryption key deal with protecting data confidentiality, not with rebuilding data after failures.