SPARQλ: SPARQL as a function

Abstract

With more and more applications providing semantic data to improve interoperability, the amount of available RDF datasets is constantly increasing. The SPARQL query language is a W3C recommendation to provide query capabilities on such RDF datasets. Yet as the coverage of RDF datasets with efficient and available SPARQL endpoints is still limited, integration of data from different RDF sources is a bottleneck that has mostly to be done in RDF consuming clients. We tackle this bottleneck by introducing SPARQ λ, an extension to the SPARQL 1.1 query language. SPARQ λ enables dynamic injection of RDF datasets during evaluation of the query, and by this lifts SPARQL to a tool to write templates for RDF producing functions in functional programming style. This is an important step to reduce the effort to write SPARQL queries that work on data from various sources. SPARQ λ is moreover suitable to directly translate to an RDF described Web service interface, which allows to lift integration of data and re-provisioning of integrated results from clients to cloud environments.