Pathfinder/MonetDB: making XQuery scale using the relational approach

Using a relational DBMS as back-end engine for an XQuery processing system leverages relational query optimization and scalable query processing strategies provided by mature DBMS engines in the XML domain. Though a lot of theoretical work has been done in this area and various solutions have been proposed, no complete systems have been made available so far to give the “hard” (practical) evidence that this is a viable approach. In this talk, I describe our first iteration of using an extensible RDBMS to build a relational XQuery processor. Performance results for the XMark benchmark show that the system is capable of evaluating XQuery queries efficiently, even if the input XML documents become huge. We additionally present further contributions such as loop-lifted staircase join, techniques to derive order properties and to reduce sorting effort in the generated relational algebra plans, as well as a method for recognizing XQuery join patterns, which – taken together – enabled us to reach our performance and scalability goals.

Speaker Details

Peter Boncz received a M.Sc. degree at the Vrije Universiteit in 1992 and a Ph.D. degree at the University of Amsterdam in 2002 with Professor Kersten, where he investigated database architecture for query-intensive applications like OLAP and Data Mining. This research led to the development of the Monet database kernel. The Monet system is used at various sites in academia for research into multimedia, GIS, XML, and medical database systems, as well as commercially by Data Distilleries, a spinoff company that creates data mining powered marketing solutions for the financial sector. Dr. Boncz was one of the co-founders of Data Distilleries, where he worked for two years as chief architect. Now at the Database Research Group of CWI (the Dutch national institute for computer science research), his research interests include: database architecture, query languages, extensibility in database systems, P2P systems, and computer architecture.

Date:
Speakers:
Peter Boncz
Affiliation:
CWI (the Dutch national institute for computer science research)