Revisiting Join Site Selection in Distributed Database Systems

Abstract

New characteristics for e-commerce applications, such as highly distributed data and unpredictable system nature, require us to revisit query processing for distributed database systems. As join operations involve relations over multiple sites, the site to carry out the join operation can have a significant impact on the performance. In this paper, we propose a new join site selection method. Our method is different from traditional methods in the following ways. First, the candidate sites are not restricted to the operand sites or query site as adopted by most database systems. Second, it considers dynamic system properties such as available bandwidth and system loads. We also conducted some experiments to offer a comparison between our method and the traditional one. The results show the advantage of our method under various system statuses. © Springer-Verlag 2003.