Keyphrases
- query answering
- ontology languages
- owl dl
- data complexity
- data exchange
- description logics
- dl lite
- answering queries
- integrity constraints
- data integration
- incomplete information
- conjunctive queries
- semantic web
- reasoning problems
- owl ontologies
- domain ontology
- reasoning systems
- formal semantics
- query rewriting
- np complete
- production rules
- data sets
- regular path queries
- conceptual models
- modal logic
- schema mappings
- logic programming