Schaffert, Dan; Meuss, Holger; Furche, Tim; Bry, François
XPath: Looking Forward.
EDBT 2002 Workshops XMLDM, MDDE, and YRWS, 24. - 28. März 2002, Prag, Tschechische Republik.
The location path language XPath is of particular importance for XML applications since it is a core component of many XML processing standards such as XSLT or XQuery. In this paper, based on axis symmetry of XPath, equivalences of XPath 1.0 location paths involving reverse axes, such as anc and prec, are established. These equivalences are used as rewriting rules in an algorithm for transforming location paths with reverse axes into equivalent reverse-axis-free ones. Location paths without reverse axes, as generated by the presented rewriting algorithm, enable efficient SAX-like streamed data processing of XPath.