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DBMS - (4) XML(Extensible Markup Language)
jacob942
2019. 6. 27. 19:10
DBMS - (4) XML(Extensible Markup Language)
structuring data의 한 방법으로서 relation model외의 또 다른 방법, XML
Extensible Markup Language(XML)
- Standard for data representation and exchange
- Document format similar to HTML
- Also streaming format
- nested구조에서 개수의 제한이 없음(flexible)
XML Basic constructus
(1) Tagged elements(nested)
(2) Attributes
(3) Text
Relation Model | XML | |
Structure | Tables | Hierarchical tree, graph |
Schema | Fixed in advance | Flexible 'self-describing' |
queries | Simple, nice language | a little hard |
ordering | none | implied |
implementation | native | add-on |
Well-formed XML
- Adhere to basic structural requirements
(1) Single root element
(2) Matched tags, proper nesting
(3) Unique attributes within elements
Reference
https://www.youtube.com/watch?v=x8kMELlNaYg&list=PL6hGtHedy2Z4EkgY76QOcueU8lAC4o6c3&index=4