Multi-query optimization in federated RDF systems

Abstract

This paper revisits the classical problem of multiple query optimization in federated RDF systems. We propose a heuristic query rewriting-based approach to share the common computation during evaluation of multiple queries while considering the cost of both query evaluation and data shipment. Furthermore, we propose an efficient method to use the interconnection topology between RDF sources to filter out irrelevant sources and share the common computation of intermediate results joining. The experiments over both real and synthetic RDF datasets show that our techniques are efficient.