Lecture Database system concepts - Chapter 10: XML

Chapter 10 describes the XML language, and then presents different ways of expressing queries on data represented in XML,and transforming XMLdata from one form to another. This chapter presents the following content: Structure of XML data, XML document schema, querying and transformation, application program interfaces to XML, storage of XML data, XML applications. | Chapter 10: XML Database System Concepts ©Silberschatz, Korth and Sudarshan See ­ for conditions on re­use XML s Structure of XML Data s XML Document Schema s Querying and Transformation s Application Program Interfaces to XML s Storage of XML Data s XML Applications Database System Concepts ­ 5th Edition, Aug 22, 2005. ©Silberschatz, Korth and Sudarshan Introduction s XML: Extensible Markup Language s Defined by the WWW Consortium (W3C) s Derived from SGML (Standard Generalized Markup Language), but simpler to use than SGML s Documents have tags giving extra information about sections of the document q . XML Introduction s Extensible, unlike HTML q Users can add new tags, and separately specify how the tag should be handled for display Database System Concepts ­ 5th Edition, Aug 22, 2005. ©Silberschatz, Korth and Sudarshan XML Introduction (Cont.) s The ability to specify new tags, and to create nested tag structures make XML a great way to exchange data, not just documents. q Much of the use of XML has been in data exchange applications, not as a replacement for HTML s Tags make data (relatively) self­documenting . A­101 Downtown 500 A­101 Johnson q Database System Concepts ­ 5th Edition, Aug 22, 2005. ©Silberschatz, Korth and Sudarshan XML: Motivation s Data interchange is critical in today’s networked world q Examples: Banking: funds transfer Order processing (especially inter­company orders) Scientific data – Chemistry: ChemML, – Genetics: BSML (Bio­Sequence Markup Language), q Paper flow of information between organizations is being replaced by electronic flow of information s .