Keyphrases
- xml data
- xml documents
- xml databases
- query optimization
- data model
- xml queries
- relational databases
- query evaluation
- query processing
- relational data
- query language
- xml schema
- keyword search
- relational and xml data
- xpath queries
- semi structured data
- xml query processing
- xml fragments
- database systems
- labeling scheme
- path expressions
- semi structured information
- hierarchical data
- queries on xml data
- xml keys
- standard for data exchange
- databases
- native xml
- xml keyword search
- xml trees
- join algorithms
- relational database systems
- cost model