QEF-LD A Query Engine for Distributed Query Processing on Linked Data

摘要

Linked data applications express integrated views using the SPARQL query language. A SPARQL federated query is submitted to a query engine that processes it over the distributed SPARQL endpoints. However, achieving an efficient execution of such a SPARQL federated query is hard. This is mainly due to the fact that query processors have little or no statistical information about the data stored at the endpoints. Moreover, the endpoints, usually, are autonomous and unstable. This paper presents QEF-LD, a query engine that enables the efficient execution of federated queries over multiple Linked Data sources. Experiments demonstrate the feasibility of QEF-LD when compared to available federated query engines.