Issue No. 03 - March (2011 vol. 23)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TKDE.2010.126
Chen Wang , IBM China Research Lab, Beijing
Tok Wang Ling , National University of Singapore, Singapore
Jiaheng Lu , Renmin University of China, Beijing
Zhifeng Bao , National University of Singapore, Singapore
As business and enterprises generate and exchange XML data more often, there is an increasing need for efficient processing of queries on XML data. Searching for the occurrences of a tree pattern query in an XML database is a core operation in XML query processing. Prior works demonstrate that holistic twig pattern matching algorithm is an efficient technique to answer an XML tree pattern with parent-child (P-C) and ancestor-descendant (A-D) relationships, as it can effectively control the size of intermediate results during query processing. However, XML query languages (e.g., XPath and XQuery) define more axes and functions such as negation function, order-based axis, and wildcards. In this paper, we research a large set of XML tree pattern, called extended XML tree pattern, which may include P-C, A-D relationships, negation functions, wildcards, and order restriction. We establish a theoretical framework about “matching cross” which demonstrates the intrinsic reason in the proof of optimality on holistic algorithms. Based on our theorems, we propose a set of novel algorithms to efficiently process three categories of extended XML tree patterns. A set of experimental results on both real-life and synthetic data sets demonstrate the effectiveness and efficiency of our proposed theories and algorithms.
Query processing, XML/XSL/RDF, algorithms, tree pattern.
Chen Wang, Tok Wang Ling, Jiaheng Lu, Zhifeng Bao, "Extended XML Tree Pattern Matching: Theories and Algorithms", IEEE Transactions on Knowledge & Data Engineering, vol. 23, no. , pp. 402-416, March 2011, doi:10.1109/TKDE.2010.126