5.2. Related work
In order to efficiently answer SPARQL queries, many stores and APIs inspired by the relational model were proposed [ERL 12, BRO 02, NEU 10, CAR 04]. x-RDF-3X [NEU 10], inspired by modern RDBMS, representing RDF triples as a large three-attribute table. The RDF query processing is boosted using an exhaustive indexing schema coupled with statistics over the data. Also, Virtuoso [ERL 12] strongly exploits the RDBMS mechanism in order to answer SPARQL queries. Virtuoso is a column-store based system that uses sorted multi-column column-wise compressed projections. Furthermore, these systems build table indexing using standard B-trees. Jena [CAR 04] supplies API for manipulating RDF graphs. Jena exploits multiple-property tables that permit multiple views of graphs and vertices, which can be used simultaneously.
The database community has recently started to investigate RDF stores based on graph data management techniques [DAS 14, ZOU 14b, KIM 15]. The work in [DAS 14] addresses...