Symmetry in XPath

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 ancestor and preceding, 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.

[1]  Klemens Böhm,et al.  Query optimization for structured documents based on knowledge on the document type definition , 1998, Proceedings IEEE International Forum on Research and Technology Advances in Digital Libraries -ADL'98-.

[2]  Peter T. Wood,et al.  Optimising Web queries using document type definitions , 1999, WIDM '99.

[3]  P. Wadler.  Two semantics for XPath , 2000 .

[4]  Zachary G. Ives,et al.  EÆcient Evaluation of Regular Path Expressions on Streaming XML Data , 2000 .

[5]  Michael J. Franklin,et al.  Efficient Filtering of XML Documents for Selective Dissemination of Information , 2000, VLDB.

[6]  Nancy Ide,et al.  XCES: An XML-based Encoding Standard for Linguistic Corpora , 2000, LREC.

[7]  Laurent Romary,et al.  CES/XML : An XML-based Standard for Linguistic Corpora , 2000 .

[8]  Abel,et al.  A formal semantics of patterns in XSLT , 2000 .

[9]  Peter T. Wood,et al.  On the Equivalence of XML Patterns , 2000, Computational Logic.

[10]  Laks V. S. Lakshmanan,et al.  Minimization of tree pattern queries , 2001, SIGMOD '01.

[11]  Tobias Kiesling.  Towards a Streamed XPath Evaluation , 2002 .

[12]  Ur Informatik.  Towards a Streamed XPath Evaluation , 2002 .

[13]  Rajeev Rastogi,et al.  Efficient filtering of XML documents with XPath expressions , 2002, Proceedings 18th International Conference on Data Engineering.

[14]  Michael A. Bodie.  The Book of Sax: The Simple API for XML , 2002 .

[15]  S. Boag,et al.  XQuery 1.0 : An XML query language, W3C Working Draft 12 November 2003 , 2003 .

[16]  Westone,et al.  Home Page , 2004, 2022 2nd International Conference on Intelligent Cybernetics Technology & Applications (ICICyTA).

[17]  Dan Suciu,et al.  Processing XML streams with deterministic automata and stream indexes , 2004, TODS.