TraPath: Fast regular path query evaluation on large-scale RDF graphs

Abstract

Regular path queries, or RPQs, are basic querying mechanisms on graphs that play an increasingly important role over the past decade. In recent years, large amounts of RDF data are published on the Web since the development of Linked Data. Such a large-scale of data has posed serious challenges to the efficiency of RPQs. In this paper, we devise a double-layer bi-directional index structure that has a linear space complexity, and propose a novel traversal-based algorithm TraPath that achieves the fast evaluation of RPQs by using the index structure. We conduct extensive experiments to evaluate and compare the performance of our prototype system and the Sesame RDF repository with a real-world RDF dataset from DBpedia. The experimental results show that TraPath significantly outperforms the state-of-the-art methods. © 2014 Springer International Publishing Switzerland.