*CANCELLED* Ontology-based Data Access: Moving Beyond Relational Data

Ontology-based data access (OBDA) is a by now well-established paradigm in which users are provided access to a data source through a conceptual view abstracts away details about how the data is organized and stored.  This conceptual view is realized through an ontology that is connected to the data source through declarative mappings.  In the last decade, OBDA has been studied extensively in the prominent case where the data source being queried is a standard relational database.  Advanced tools are available that support query processing in OBDA systems, and OBDA has been applied in many real-world scenarios in industry and in public administrations.  However, the need has emerged for extending OBDA to novel types of datasources.  In this talk, we deal with three such extensions, namely geo-spatial data, temporal data, and tree-structured data.  We discuss the challenges that these extensions pose for OBDA, and we present recent developments on how to incorporate such novel forms of data into state-of-the-art OBDA systems.  The techniques we present are currently being incorporated into the state-of-the-art OBDA system Ontop, developed at the Free University of Bozen-Bolzano.