DL-Lite with Attributes, Datatypes and Sub-Roles (Full Version)

We extend the tractable DL-Lite languages by (i) relaxing the restriction on the allowed interaction between cardinality constraints and role inclusions; (ii) extending the languages with attributes and datatypes. On the one hand, we push the limits of the use of cardinality constraints over role hierarchies and also show effects of the ABox on allowed cardinality constraints. On the other hand, attributes—a notion borrowed from data models—associate concrete values from datatypes to abstract objects and in this way complement DL-Lite roles, which describe relationships between abstract objects. We present complexity results for two most important reasoning problems in DL-Lite: combined complexity of knowledge base satisfiability and data complexity of positive existential query answering.