Group-oriented catalog allocation in heterogeneous distributed database systems

The catalog is a system database, which contains information regarding various objects that an of interest to the system itself In heterogeneous distributed database systems (HDDBSs), efficient handling of the global catalog is of great practical importance with respect to the site autonomy, global query optimization, global view management, authorization mechanism, and data distribution transparency, In this paper, we propose a new catalog allocation scheme, named GOCAS (group-oriented catalog allocation scheme). GOCAS can reduce the number of inter-site messages for accessing catalog information by exploiting the locality of references that span a number of sites. This approach is contrary to the previous catalog allocation schemes, where the locality of references cannot be employed or can be applied restrictively to only one site. We develop an analytical model in order to compare the performance of GOCAS to other schemes. With the analytical model, we describe the performance benefits of GOCAS and its effectiveness to other schemes.