24th of March 2005Deferred Incremental Refresh of XML Materialized Views1 COMPSCI 732 – Software Tools and Techniques Deferred Incremental Refresh of XML Materialized Views The University Of Auckland Thursday the 24th of March 2005 Deferred Incremental Refresh of XML Materialized Views Hyunchul Kang Hosang Sung ChanHo Moon Hyunchul Kang Hosang Sung ChanHo Moon

24th of March 2005Deferred Incremental Refresh of XML Materialized Views2 Introduction - Presentation - Project - Management - Method Organization - Company Hierarchy - Team Hierarchy - Project Hierarchy Process - Project Initiation - Keeping Control - Project Evaluation Conclusion - Review - Extensions Questions Introduction A World Wide Information Era Why is information so important? Resource for the companies Value for the companies What kind of information? How to exchange this information? Relational Database Semi structured Database

24th of March 2005Deferred Incremental Refresh of XML Materialized Views3 Introduction eXternal Markup Language What is XML? Difference between XML and HTML XML is free XML is extensible Why XML? When XML? Where XML?

24th of March 2005Deferred Incremental Refresh of XML Materialized Views4 Introduction XML Materialized Views What is a view? The result of a query XQuery What is a materialized view? A copy, a cache of the data in the database How to maintain a view? Complete recalculation Incremental refresh Introduction Victim Cache - Idea 1 - Idea 2 - Idea 3 Simple Scallar - Idea 1 - Idea 2 - Idea 3 Experiments - Experience 1 - Experience 2 - Experience 3 - Experience 4 Conclusion Questions

24th of March 2005Deferred Incremental Refresh of XML Materialized Views5 Introduction Agenda Introduction Victim Cache - Idea 1 - Idea 2 - Idea 3 Simple Scallar - Idea 1 - Idea 2 - Idea 3 Experiments - Experience 1 - Experience 2 - Experience 3 - Experience 4 Conclusion Questions Presentation Document Management System Storage System Update Information System Algorithms Information Generation Algorithm Reflection Algorithm Performance and Conclusion

24th of March 2005Deferred Incremental Refresh of XML Materialized Views6 Presentation Work Presentaion Work Presentation Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions

24th of March 2005Deferred Incremental Refresh of XML Materialized Views7 Presentation Management Areas Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions XML DTD XML DTD XML DTD XML Base Document Manager Base XML Document Area XML Materialized View Manager XML Materialized View Area View 1 View 2 View 4 View 5 View 3

24th of March 2005Deferred Incremental Refresh of XML Materialized Views8 Presentation Storage Areas Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions DTDIDDIDEIDEnameContent 1101paper title Deferred Incremental Refresh of XML Materialized Views authorH. Kang, H. Sung, and C. Moon sectionIntroduction paragraphIn database systems, the view has been useful and … paragraphViews are often materialized for query performance … sectionRelated Work paragraph When the XML documents are stored in the RDBMS … 1202paper title Aggregate Path Index for incremental Web view maintenance …………… XElem Table

24th of March 2005Deferred Incremental Refresh of XML Materialized Views9 Presentation Storage Areas Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions ViewID ViewDef DTDID PCETE V1 Contains(“ XML”) title {title, author} 1 V2 Contains(“ Path”) title {title, author} 1 …………… ViewIDDIDBaseEIDContent V101paper- V10101titleDeferred Incremental Refresh of XML Materialized Views V10102authorH. Kang, H. Sung, and C. Moon V202paper V20201title Aggregate Path Index for incremental Web view maintenance ………… ViewInfo Table ViewElem Table

24th of March 2005Deferred Incremental Refresh of XML Materialized Views10 Presentation Storage Areas Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions ViewIDDTDIDFirstROffsetDIDList V11150{1} V21200{2} ………… ViewRefresh Table

24th of March 2005Deferred Incremental Refresh of XML Materialized Views11 Presentation Update Information Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions XML DTD XML DTD XML DTD XML Base Document Manager Base XML Document Area XML Materialized View Manager XML Materialized View Area View 1 View 2 View 4 View 5 View 3 ViewInfo Table ViewElem Table XMLElem Table ViewRefresh Table Update Log File

24th of March 2005Deferred Incremental Refresh of XML Materialized Views12 Algorithms Different Algorithms? Different ALGORITHMS Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions

24th of March 2005Deferred Incremental Refresh of XML Materialized Views13 Algorithm Generation Algorithm Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions Generation Algorithm XMLElem Table ViewRefresh Table Update Log File XML DTD XML Materialized View Refresh Instruction Insert Delete Modify

24th of March 2005Deferred Incremental Refresh of XML Materialized Views14 Algorithm Reflexion Algorithm Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions Reflexion Algorithm ViewElem Table XML Materialized View Refresh Instruction Insert Delete Modify

24th of March 2005Deferred Incremental Refresh of XML Materialized Views15 Conclusion CONCLUSION Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions

24th of March 2005Deferred Incremental Refresh of XML Materialized Views16 Conclusion Performance Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions incremental refresh view recomputation Retrieval Time % of document update

24th of March 2005Deferred Incremental Refresh of XML Materialized Views17 Conclusion Why read this paper? Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions “This implies that XML view materialization would be very effective in providing the database like services out of a large-scale XML warehouse.” H. Kang, H. Sung, and C. Moon Deferred Incremental Refresh of XML Materialized Views: Algorithms and Performance Evaluation

24th of March 2005Deferred Incremental Refresh of XML Materialized Views18 Questions Any Questions? Any QUESTIONS? Introduction - Information Era - XML - Views - Agenda Presentation - Management - Storage - Update Algorithms - Generation - Reflexion Conclusion - Performance Questions