13.5. Recovery Techniques
Database recovery techniques used by DBMS depend on the type and extent of damage that has occurred to the database. These techniques are based on the atomic transaction property. All portions of transactions must be treated as a single logical unit of work, in which all operations must be applied and completed to produce a consistent database. The following two types of damages can take place to the database:
Physical damage: If the database has been physically damaged, for example disk crash has occurred, then the last backup copy of the database is restored and update operations of committed transactions are reapplied using the transaction log file. It is to be noted that the restoration in this case is possible ...
Get Database Systems: Concepts, Design and Applications now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.