Keyphrases
- labeling scheme
- xml data
- xml documents
- xml queries
- xml databases
- xml query processing
- data model
- query optimization
- query evaluation
- relational data
- query processing
- relational databases
- xml schema
- query language
- keyword search
- relational database systems
- transitive closure
- xpath queries
- databases
- semi structured data
- xml trees
- database
- efficient processing
- structured data
- database systems
- native xml databases