On Equality-Generating Dependencies in Ontology Querying - Preliminary Report
نویسندگان
چکیده
In ontology-based data access, data are queried through an ontology that offers a representation of the domain of interest. In this context, correct answers are those entailed by the logical theory constituted by the data and the ontology. Traditional database constraints like tuple-generating dependencies (TGDs) and equality-generating dependencies (EGDs) are a useful tool for ontology specification. However, their interaction usually leads to intractability or undecidability of query answering; separability is the notion that captures the lack of interaction between TGDs and EGDs. In this paper we exhibit a novel and general sufficient condition for separability, in the case where the ontology is expressed with inclusion dependencies (a subclass of TGDs) and EGDs.
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