XPath结构连接顺序优化-计算机科学与探索.PDF

ISSN 1673-9418 CODEN JKYTA8 E-mail: fcst@ Journal of Frontiers of Computer Science and Technology 1673-9418/2010/04(11)-1049-08 Tel: +86-10 DOI: 10.3778/j.issn.1673-9418.2010.11.010 XPath 1+ 2 , 1. , 510006 2. , 510006 Structural Join Order Optimization for XPath LI Dong1+, KUANG Zimin2 1. School of Software, South China University of Technology, Guangzhou 510006, China 2. School of Computer Science and Engineering, South China University of Technology, Guangzhou 510006, China + Corresponding author: E-mail: cslidong@ LI Dong, KUANG Zimin. Structural join order optimization for XPath. Journal of Frontiers of Computer Science and Technology, 2010, 4(11): 1049-1056. Abstract: XQuery proposed by W3C is the standard query language for XML. XPath is the main part of XQuery. While using XQuery language, a large part of execution time is spent on the evaluation of XPath. This paper pro- poses a cost estimation based algorithm for XPath structural join order optimization. Experimental results show that this algorithm can get better effect of query optimization. Key words: XPath; structural join; cost estimation; hierarchy encoding; dynamic programming XQuery W3C XML XPath XQuery , XQuery XPath , , ; , ; ; ; ; Received 2010-05, Accepted 2010-07. 1050 Journal of Frontiers of Computer Science and Technology 2010, 4(11) A TP311 1