Keyphrases
- query answering
- dl lite
- knowledge base
- data exchange
- data complexity
- data integration
- conjunctive queries
- description logics
- integrity constraints
- answering queries
- query rewriting
- inconsistent databases
- incomplete information
- data integration systems
- knowledge representation
- knowledge based systems
- logic programming
- open world
- expert systems
- query containment
- ontology languages
- special case
- ontology based data access
- query answers
- datalog programs
- xml data exchange