Algorithms for reducing rollbacks in concurrency control by certification

In this paper, we present concurrency control schemes, based on the optimistic approach, which aim at reducing the rate of rollbacks, tolerating higher degrees of conflict among transactions, and allowing more concurrency at the update phase. Both the single site and fully duplicated database networks are considered. Performance results of the proposed approach are presented. The protocols offer a good tool to improve the throughput of optimistic concurrency control methods and to widen their scope of applicability.