Keyphrases
- query language
- efficient processing
- data model
- query evaluation
- relational algebra
- processing queries
- expressive power
- query processing
- xml query languages
- database
- aggregation queries
- real time
- algebraic operations
- object oriented
- object oriented databases
- relational data model
- conjunctive queries
- data processing
- response time
- database query languages
- indexing techniques
- query interface
- schema evolution
- join queries
- web search engines
- aggregate functions
- data sources
- information retrieval