A SPARQL extension for generating RDF from heterogeneous formats

International audienceRDF aims at being the universal abstract data model for structureddata on the Web. While there is effort to convert data in RDF, the vast majorityof data available on the Web does not conform to RDF. Indeed, exposing datain RDF, either natively or through wrappers, can be very costly. Furthermore,in the emerging Web of Things, resource constraints of devices prevent fromprocessing RDF graphs. Hence one cannot expect that all the data on the Webbe available as RDF anytime soon. Several tools can generate RDF from non-RDF data, and transformation or mapping languages have been designed to offermore flexible solutions (GRDDL, XSPARQL, R2RML, RML, CSVW, etc.). Inthis paper, we introduce a new language, SPARQL-Generate, that generates RDFfrom: (i) a RDF Dataset, and (ii) a set of documents in arbitrary formats. AsSPARQL-Generate is designed as an extension of SPARQL 1.1, it can provably:(i) be implemented on top on any existing SPARQL engine, and (ii) leverage theSPARQL extension mechanism to deal with an open set of formats. Furthermore,we show evidence that (iii) it can be easily learned by knowledge engineers thatknow SPARQL 1.1, and (iv) our first naive open source implementation performsbetter than the reference implementation of RML for big transformations