Keyphrases
- database
- query processing
- databases
- query interface
- data structure
- xpath queries
- keywords
- database schema
- data model
- data sources
- class hierarchies
- theoretical framework
- query evaluation
- semantically equivalent
- retrieval method
- user defined
- user interaction
- query expansion
- search queries
- query rewriting
- transformation rules
- relational tables
- response time
- access paths