期刊名称:International Journal of Electronics Communication and Computer Engineering
印刷版ISSN:2249-071X
电子版ISSN:2278-4209
出版年度:2012
卷号:3
期号:5
页码:1234-1237
出版社:IJECCE
摘要:An XML database is a data persistence software system that allows data to be stored in XML format. This data can then be queried, exported and serialized into the desired format. XML databases are usually associated with document-oriented databases. The XML documents are usually modelled as trees and queries in XML query languages and are typically twig (or small tree) patterns with some nodes having value-based predicates. Therefore, finding all distinct matching’s of a twig pattern becomes a core operation in an XML query evaluation. This paper presents two algorithms for XML tree pattern matching. The TwigStack algorithm is used to compute answers to a query twig pattern. This algorithm solves the problem of larger intermediate results with decompositionmatching-merging methods. When the patterns have only ancestor-descendant edges, the intermediate result of each path matching is guaranteed to be part of the final result. The TreeMatch algorithm defines an extended XML tree pattern (twig) means P-C, A-D, negation, wildcard and order restriction. This algorithm provides tree matching for class
关键词:Query processing; Tree pattern matching; Twigs; XML