Recovery Algorithms Recovery algorithms are techniques to ensure database consistency and transaction atomicity and durability despite failures Focus of this chapter Recovery algorithms have two parts 1.Actions taken during normal transaction processing to ensure enough information exists to recover from failures 2.Actions taken after a failure to recover the database contents to a state that ensures atomicity,consistency and durability Database System Concepts,5th Edition,Oct 5,2006 17.4 ©Silberschat乜，Korth and SudarshanDatabase System Concepts, 5 17.4 ©Silberschatz, Korth and Sudarshan th Edition, Oct 5, 2006 Recovery Algorithms Recovery algorithms are techniques to ensure database consistency and transaction atomicity and durability despite failures Focus of this chapter Recovery algorithms have two parts 1. Actions taken during normal transaction processing to ensure enough information exists to recover from failures 2. Actions taken after a failure to recover the database contents to a state that ensures atomicity, consistency and durability