Scalable XQuery Type Matching
Publication Details
| Title |
Scalable XQuery Type Matching |
| Authors |
Jens Teubner |
| Published |
Proceedings 11th Int'l Conference on Extending Database Technology
(EDBT) |
| Download |
paper (PDF),
presentation slides (PDF) |
| Abstract |
XML Schema awareness has been an integral part of the XQuery language
since its early design stages. Matching XML data against XML types is
the main operation that backs up XQuery type expressions, such as
typeswitch, instance of, or certain XPath operators.
This interaction is particularly vital in data-centric XQuery
applications, where data come with detailed type information from an
XML Schema document.
So far there has been little work on the optimization of those
operations. This work presents an efficient implementation of the
runtime aspects of XML Schema support. We propose type ranks
as a novel and uniform way to implement all facets of type matching in
the W3C XQuery Recommendation. As a concise encoding of the type
hierarchy defined by an XML Schema document, type ranks minimize the
cost of checking the runtime type of XQuery singleton items. By
aggregating type ranks, we leverage the grouping capabilities
of modern DBMS implementations to efficiently execute type matching on
XQuery sequences. In addition, we improve the complexity bounds
incurring with typeswitch expressions over existing
approaches. Experiments on an off-the-shelf database system
demonstrate the potential of our approach. |
Publication Log
| December 2007 |
camera-ready for EDBT 2007
|
| September 2007 |
submission to EDBT 2008 (accepted)
|
