Analysis of Recovery Techniques in Data Base Management System

摘要

As system continue to grow in size and complexity, they pose increasingly greater safety and risk management challenges. The danger of data being corrupted due to reckless application writes is increased. When a DBMScrashes, all or a portion of the data may become unusable. Appropriate procedures must be followed to restore, validate and return the system to normal. Recovery algorithms are techniques to ensure database consistency and transaction atomicity and durability despite failure. In this paper, we have studied when a user face the problems of failure, he may confuse which technique should be used. So we compare the recovery techniques Log Based Scheme and Shadow Paging on the basis of their performance. A review of recovery techniques give the idea of modifying log based recovery technique to be used in multi-user environment more precisely if some problem of writing log each time might be solved. Shadow paging is an alternative approach in place of log based scheme Shadow paging may be considered to use for recovering if its drawbacks of garbage collection and data fragmentation may resolve.