Benjamin Cogrel
Ontopic s.r.l.
Prior to Ontopic, Benjamin Cogrel was a researcher at the KRDB Research Centre for Knowledge and Data, Faculty of Computer Science, Free University of Bozen-Bolzano. He is one of the maintainers of Ontop, to which he has continuously been contributing for more than six years.

2021 Workshops and Tutorials: Integrating Data through Virtual Knowledge Graphs with Ontop

Recently, knowledge graphs have been successfully deployed to overcome the typical difficulties in accessing and integrating data stored in different kinds of sources. In particular, in the Virtual Knowledge Graph (VKG) approach, data is presented in the form of a graph, which is mapped to the underlying data sources, and query answering is based on advanced query transformation techniques. In this tutorial we illustrate the principles underlying the VKG approach, providing an overview of well-established algorithms and techniques, and we discuss relevant use-cases using VKGs. We also provide a step-by-step hands-on session, where participants can experiment on their own with the discussed technologies using the open-source VKG system Ontop ( and other open-source tools.