Keyphrases
- query answering
- data exchange
- data complexity
- integrity constraints
- data integration
- incomplete information
- conjunctive queries
- answering queries
- query rewriting
- semantic web
- natural language
- semantic information
- inconsistent databases
- xml data exchange
- data sources
- dl lite
- query relaxation
- domain ontology
- knowledge representation
- datalog programs
- data sets
- query containment
- regular path queries
- data integration systems
- open world