Query-Specific Pruning of RML Mappings (Extended Version)

Abstract

Current approaches for knowledge graph construction with RML focus on full RDF graph materialization without considering user queries, which is inefficient in dynamic query environments where often only a specific subset of the full graph is needed to answer a given query. This paper introduces an approach to prune RML mappings such that the resulting partially-materialized graph is still sufficient to answer a given SPARQL query completely. By evaluating the approach based on a well-know RML materialization benchmark, we show that such pruning significantly reduces both the materialization time and the size of the produced graph, while also noticeably reducing querying time