PRESERVING DATA AND MANAGING CONCURRENCY IN DISTRIBUTED DATABASE

A distributed database can reside on organized network servers or decentralized independent computers on the Internet, on corporate intranets or extranets. Because Distributed databases store data across multiple computers, distributed databases may improve performance at end-user worksites by allowing transactions to be processed on many machines, instead of being limited to one. As distributed database isthe current trending technology, the Preservation of data becomes the serious issue. The access control and the integrity of the system needs to be taken care. Here, we propose solutions for preserving data by providing multilevel access control, concurrent access, reliability, integrity and recovery that pertain to a distributed database system. This paper focus on algorithm based on concurrency control such as basic timestamp algorithm, distributed two phase locking protocol (2PL), distributed optimistic protocol, Deadlock algorithm.