Abstract
In this article, we address the issues which are related to the cost-based XML query optimization for XPath. Specially, we focus on the issue of how to determine the execution order for a given XPath expression according to the cost models. The main impact factor that dominates the execution order is the size of the intermediate results during the evaluation of queries. The hierarchy encoding scheme and the value-encoding histogram are introduced to support the size estimation of the path expressions. Two cost models are proposed to describe the costs of different types of join operations in the path expressions. A heuristic-based dynamic programming approach is proposed to determine the optimal execution tree. The primary experimental results demonstrate the validity of our approaches.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
