Departmental Papers (CIS)

An Efficient XPath Query Processor for XML Streams

Yi Chen, Arizona State University
Susan B. Davidson, University of Pennsylvania
Yifeng Zheng, University of Pennsylvania

Document Type Conference Paper

Conference 2006 IEEE. Reprinted from Proceedings of the 22nd International Conference on Data Engineering, ICDE 2006, April 2006, 12 pages.
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Streaming XPath evaluation algorithms must record a potentially exponential number of pattern matches when both predicates and descendant axes are present in queries, and the XML data is recursive. In this paper, we use a compact data structure to encode these pattern matches rather than storing them explicitly. We then propose a polynomial time streaming algorithm to evaluate XPath queries by probing the data structure in a lazy fashion. Extensive experiments show that our approach not only has a good theoretical complexity bound but is also efficient in practice.


Date Posted: 13 February 2007

This document has been peer reviewed.