Keyphrases
- query language
- document centric
- information retrieval
- data model
- database
- object oriented
- query execution plan
- query evaluation
- expressive power
- complex objects
- relational algebra
- text retrieval
- query expansion
- recursive queries
- database manager
- database systems
- relevance feedback
- information retrieval systems
- regular expressions
- relational model
- information access
- structured documents
- transitive closure
- rdf data
- retrieval model
- query optimization
- xml data