SPARQL Update queries over R2RML mapped data sources

Abstract

In the Linked Data Life Cycle mapping and extracting data from structured sources is an essential step in building a knowledge graph. In existing data life cycles this process is unidirectional, i.e. the data is extracted from the source but changes like cleaning and linking are not fed back into the originating system. SPARQL-to-SQL rewriters create virtual RDF without materializing data by exposing SPARQL endpoints. With the Update extension of our SparqlMap system we provide read/write access to structured data sources to enable a tighter integration of the source systems in knowledge refinement process. in this paper, we discuss three different update methods and further describe in two scenarios how the source system can benefit from feed back from the Linked Data integration.