A generic subsumption testing toolkit for knowledge base queries
Subsumption checking is a key technique for intensional reasoning in data and knowledge bases, with applications in terminology management, schema integration, query optimization, reuse of materialized views, and cooperative question-answering. However, the demands of these applications differ, and general solutions covering all these aspects are undecidable or at least computationally intractable. We have therefore implemented a generic approach from which subsumption testers can be configured by tuning certain parameters. Specific contributions include a coverage of negation and the exploitation of semantic knowledge. An application in the ConceptBase system, a deductive object manager for meta data, indicates the practical usefulness of the approach.
KeywordsIntegrity Constraint Conditional Fact Query Optimization Conjunctive Query Deductive Database
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