Abstract
This poster shows an ontology-mediated query answering system (gOWL) based on pure materialization to avoid query rewriting online. gOWL shows that answering queries over a partial materialization of the chase is complete for a large fragment of practical queries with bounded depth. From a system engineering perspective, the materialization approach allows us to design a modular architecture to integrate off-the-shelf efficient SPARQL query engines. The poster will be based on DBpedia and UOBM datasets. We will compare the performance of gOWL with PAGOdA, Ontop, and Pellet (with speedup up to three orders of magnitude).