Keyphrases
- query rewriting
- view definitions
- conjunctive queries
- queries using views
- query evaluation
- query answering
- query optimization
- regular path queries
- view selection
- query containment
- xpath queries
- data integration
- query language
- tree patterns
- database
- spatial databases
- xml queries
- query processing
- query execution
- integrity constraints
- database views
- query result
- answering queries using views
- rewriting rules
- aggregate queries
- materialized views
- data complexity
- relational data
- special case
- statistical databases
- database queries
- query logs
- answering queries
- data exchange
- expressive power
- rewrite rules
- np complete
- data sources
- data model
- search engine
- aggregate views
- databases