Efficient mining of frequent XML query patterns with repeating-siblings

• Published in: Information and software technology Vol. 50; no. 5; pp. 375 - 389
• Main Authors: Yang, Liang Huai, Lee, Mong Li, Hsu, Wynne, Huang, Decai, Wong, Limsoon
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.2008; Elsevier Science Ltd
• Subjects: Algorithms; Data mining; Extensible Markup Language; Frequent pattern mining; Structured pattern; Studies; Systems design; Tree pattern mining; XML query pattern; Frequent pattern mining; Structured pattern; XML query pattern; Tree pattern mining
• ISSN: 0950-5849; 1873-6025
• DOI: 10.1016/j.infsof.2007.02.019

A recent approach to improve the performance of XML query evaluation is to cache the query results of frequent query patterns. Unfortunately, discovering these frequent query patterns is an expensive operation. In this paper, we develop a two-pass mining algorithm 2 PXMiner that guarantees the discovery of frequent query patterns by scanning the database at most twice. By exploiting a transaction summary data structure, and an enumeration tree, we are able to determine the upper bounds of the frequencies of the candidate patterns, and to quickly prune away the infrequent patterns. We also design an index to trace the repeating candidate subtrees generated by sibling repetition, thus avoiding redundant computations. Experiments results indicate that 2 PXMiner is both efficient and scalable.