Concurrency Control in Distributed Database Management System (Case Study in Online Shopping System)

Abstract

Distributed Database Management System (DDBMS) is becoming interested due to the declining cost of computer hardware and geographically dispersed organizations where data processing is increased. A distributed database is a collection of multiple interconnected databases, which are spread physically across different locations that communicate via a computer network. One of the main problems in DDBMS is concurrency control problem. The main objective of concurrency control is to ensure that there is no interference when two or more users access a shared database simultaneously. In this system, the problems of concurrent access are studied on Online Shopping System. The system firstly implements distributed online shopping databases across 3 different sites and the data are allocated by using primary horizontal fragmentation. In Distributed Database Management System, concurrency control problem is solved with 2 phase locking method with lock manager. The original 2 phase locking has cascading rollback and deadlock. Therefore, this proposed system uses rigorous 2 phase locking with distributed lock manager to solve cascading rollback and wound-wait deadlock avoidance scheme is used to solve deadlock. Microsoft SQL Server 2016, and Java Platform, Enterprise Edition (J2EE) programming language are used to implement this system.