Heuristic Algorithms for Fragment Allocation in a Distributed Database System

Abstract

Communication costs caused by remote access and retrieval of table fragments accessed by queries is the main part execution cost of the distributed database queries. Data Allocation algorithms try to minimize this cost by assigning fragments at or near the sites they may be needed. Data Allocation Problem (DAP) is known to be NP-Hard and this makes heuristic algorithms desirable for solving this problem. In this study, we design a model based on Quadratic Assignment Problem (QAP) for the DAP. The QAP is a well-known problem that has been applied to different problems successfully. We develop a set of heuristic algorithms and compare them with each other through experiments and determine the most efficient one for solving the DAP in distributed databases.