IncMap: pay as you go matching of relational schemata to OWL ontologies

Ontology Based Data Access (OBDA) enables access to relational data with a complex structure through ontologies as conceptual domain models. A key component of an OBDA system are mappings between the schematic elements in the ontology and their correspondences in the relational schema. Today, in existing OBDA systems these mappings typically need to be compiled by hand, which is a complex and labor intensive task. In this paper we address the problem of creating such mappings and present IncMap, a system that supports a semi-automatic approach for matching relational schemata and ontologies. Our approach is based on a novel matching technique that represents the schematic elements of an ontology and a relational schema in a unified way. IncMap is designed to work in a query-driven, pay as you go fashion and leverages partial, user-verified mappings to improve subsequent mapping suggestions. This effectively reduces the overall effort compared to compiling a mappings in one step. Moreover, IncMap can incorporate knowledge from user queries to enhance suggestion quality.