Keyphrases
- xml data
- approximate query answering
- query evaluation
- query processing
- query language
- approximate answers
- xpath queries
- query optimization
- xml documents
- xml queries
- queries on xml data
- answering queries
- data model
- efficient query processing
- querying xml data
- query result
- aggregate queries
- xml databases
- path expressions
- relational databases
- xml query processing
- xml trees
- selectivity estimation
- relational database systems
- regular path expressions
- tree pattern queries
- xml views
- relational data
- path queries
- xml schema
- semi structured information
- native xml databases
- xml query languages
- database systems
- semi structured data
- query decomposition
- xml fragments
- query rewriting
- multi dimensional
- cost model
- tree patterns
- xml elements
- xpath expressions
- keyword search
- database
- relational and xml data
- index structure
- range queries
- conjunctive queries
- query answers
- recursive queries
- relational tables
- labeling scheme
- complex queries
- xml data sources
- query answering
- efficient processing
- web search engines
- transitive closure
- databases