As the popularity of XML (extensible Markup Language) keeps growing rapidly,the management of XML compliant structured-document databases has become a very interesting andcompelling research area. Query optimization f...As the popularity of XML (extensible Markup Language) keeps growing rapidly,the management of XML compliant structured-document databases has become a very interesting andcompelling research area. Query optimization for XML structured-documents stands out as one of themost challenging research issues in this area because of the much enlarged optimization (search)space, which is a consequence of the intrinsic complexity of the underlying data model of XML data.We therefore propose to apply deterministic transformations on query expressions to mostaggressively prune the search space and fast achieve a sufficiently improved alternative (if not theoptimal) for each incoming query expression. This idea is not just exciting but practicallyattainable. This paper first provides an overview of our optimization strategy, and then focuses onthe key implementation issues of our rule-based transformation system for XML query optimization ina database environment. The performance results we obtained from experimentation show that ourapproach is a valid and effective one.展开更多
文摘As the popularity of XML (extensible Markup Language) keeps growing rapidly,the management of XML compliant structured-document databases has become a very interesting andcompelling research area. Query optimization for XML structured-documents stands out as one of themost challenging research issues in this area because of the much enlarged optimization (search)space, which is a consequence of the intrinsic complexity of the underlying data model of XML data.We therefore propose to apply deterministic transformations on query expressions to mostaggressively prune the search space and fast achieve a sufficiently improved alternative (if not theoptimal) for each incoming query expression. This idea is not just exciting but practicallyattainable. This paper first provides an overview of our optimization strategy, and then focuses onthe key implementation issues of our rule-based transformation system for XML query optimization ina database environment. The performance results we obtained from experimentation show that ourapproach is a valid and effective one.
