Question

Explain log base recovery.

Answer 1

Log-based Recovery. Log is a sequence of records, which maintains the records of actions performed by a transaction. It is important that the logs are written prior to the actual modification and stored on a stable storage media, which is failsafe.

Answer 2

Deferred database modification − All logs are written on to the stable storage and the database is updated when a transaction commits.

Immediate database modification − Each log follows an actual database modification. That is, the database is modified immediately after every operation.