Publication
Title
Satisfiability of XPath queries with sibling axes
Author
Abstract
We study the satisfiability problem for XPath fragments supporting the following-sibling and preceding-sibling axes. Although this problem was recently studied for XPath fragments without sibling axes, little is known about the impact of the sibling axes on the satisfiability analysis. To this end we revisit the satisfiability problem for a variety of XPath fragments with sibling axes, in the presence of DTDs, in the absence of DTDs, and under various restricted DTDs. In these settings we establish complexity bounds ranging from NLOGSPACE to undecidable. Our main conclusion is that in many cases, the presence of sibling axes complicates the satisfiability analysis. Indeed, we show that there are XPath satisfiability problems that are in PTIME and PSPACE in the absence of sibling axes, but that become NP-hard and EXPTIME-hard, respectively, when sibling axes are used instead of the corresponding vertical modalities (e.g., the wildcard and the descendant axis).
Language
English
Source (journal)
Lecture notes in computer science
Publication
2005
Volume/pages
3774(2005), p. 122-137
Full text (Publishers DOI)
UAntwerpen
Faculty/Department
Publication type
Subject
External links
Record
Identification
Creation 14.01.2014
Last edited 02.09.2016