Optimizing SPARQL queries over disparate RDF data sources through distributed semi-joins

Abstract

With the ever-increasing amount of data on the Web available at SPARQL endpoints [1] the need for an integrated and transparent way of accessing the data has arisen. It is highly desirable to have a way of asking SPARQL queries that make use of data residing in disparate data sources served by multiple SPARQL endpoints. We aim at providing such a capability and thus enabling an integrated way of querying the whole Semantic Web at a time.