Efficient Graph Reachability Query Answering Using Tree Decomposition

Efficient reachability query answering in large directed graphs has been intensively investigated because of its fundamental importance in many application fields such as XML data processing, ontology reasoning and bioinformatics. In this paper, we present a novel indexing method based on the concept of tree decomposition. We show analytically that this intuitive approach is both time and space efficient. We demonstrate empirically the efficiency and the effectiveness of our method.