All databases have logs associated with them which keep a record of changes to the database. Lets consider IBM DB2 database for understanding the database logging techniques.
A database that uses archival logging can be backed up online. To reach a specified point in time, you can perform a rollforward recovery. A database that uses archival logging is therefore also called recoverable.There is another type of logging , Circular logging which keeps all restart data in a ring of log files. It starts logging in first file in the ring, then... [More]