Keyphrases
- query processing
- database
- user queries
- response time
- database queries
- keywords
- data structure
- range queries
- description logics
- information retrieval systems
- np complete
- retrieval systems
- information retrieval
- query evaluation
- query formulation
- attribute values
- relevance feedback
- data sources
- original query
- efficient processing
- query execution
- logical implication
- query interface
- complex queries
- result set
- communication cost
- query terms
- vector space
- user defined
- user interaction