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XML Data Storage. Joe Carroll Russell Gibbons. Agenda. What is XML Storage of XML Benefits of XML Databases Problems with XML Databases Discussion. What is XML.
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XML Data Storage Joe Carroll Russell Gibbons
Agenda • What is XML • Storage of XML • Benefits of XML Databases • Problems with XML Databases • Discussion
What is XML “XML (Extensible Markup Language) is a W3C initiative that allows information and services to be encoded with meaningful structure and semantics that computers and humans can understand. XML is great for information exchange, and can easily be extended to include user-specified and industry-specified tags.” www.orafaq.com/glossary/faqglosx.htm
Storage of XML • Character • Relational (shredded) • Native XML
Character • Storage options • Large character fields in DBMS • Flat files • .xml files • Fast insert & retrieval • Poor search
Relational • Data still stored as character • Portions of the data extracted into additional relational tables • Increased parse time • Increased search capabilities
Native XML • Exclusive XML DBMS • Sedna • Timber • Integrated XML DBMS • DB2 • Oracle
Native XML Benefits • XML messages stored in their original format • Documents can be transformed straight from the database via XPath or XSLT. • Increased search capabilities for documents that must be stored as XML.
Native XML Problems • Same problems as hierarchical databases • Many-to-many relationships • Referential Integrity • Difficult to handle within legacy applications. • Increased CPU consumption.
References • [1] Shalaka Natu, John Mendonca, “Digital Asset Management Using A Native XML Database Implementation”, CITC4 ’03, October 16-18, 2003, Lafayette, Indiana, USA. • [2] Matthias Nicola, Jasmi John, “XML Parsing: A Threat to Database Performance”, CIKM ’03, November 3-8, 2003, New Orleans, Louisiana, USA. • [3] Mattias Nicola, Bert van der Linden, “Native XML Support in DB2 Universal Database”, Proceedings of the 31st VLDB Conference, Trondheim, Norway, 2005. • [4] “Native XML data store overview”, http://publib.boulder.ibm.com/infocenter/db2luw/v9/topic/com.ibm.db2.udb.apdv.embed.doc/doc/c0022308.htm • [5] “Use XML databases to empower Java Web services”, http://www.javaworld.com/javaworld/jw-12-2004/jw-1206-xml.html