A vital problem that should be tackled in today’s database system is guaranteeing database consistency. Many techniques and tools have been devised to fulfill this requirement in many interrelated research areas such as concurrency control, security control, reliability control, and integrity control (Eswaran & Chamberlin, 1975; Grefen, 1993). Concurrency control deals with the prevention of inconsistencies caused by concurrent access by multiple users or applications to a database. Security control deals with preventing users from accessing and modifying data in a database in unauthorized ways. Reliability control deals with the prevention of errors due to the malfunctioning of system hardware or software. Integrity control deals with the prevention of semantic errors made by users due to their carelessness or lack of knowledge. This chapter is concerned only with integrity control.
Multi-version concurrency control scheme for a database system