Keyphrases
- xml schema
- specification language
- programming language
- xml documents
- formal specification
- regular expressions
- object oriented
- xml data
- description language
- data exchange
- metadata
- integrity constraints
- relational databases
- semi structured documents
- conceptual model
- building blocks
- regular tree languages
- structured data
- artificial intelligence
- databases
- general purpose
- search engine
- relational schema
- machine learning