We give semantic characterizations of the expressive power of navigational XPath (a.k.a. Core XPath) in terms of first order logic. XPath can be used to specify sets of nodes and sets of paths in an XML document tree. We consider both uses. For sets of nodes, XPath is equally expressive as first order logic in two variables. For paths, XPath can be defined using four simple connectives, which t...

XPath is widely used as an XML query language and is embedded in XQuery expressions and in XSLT stylesheets. In this paper, we propose a rule set which logically simplifies XPath queries by using a heuristic method in order to improve the processing time. Furthermore, we show how to substitute the XPath 2.0 intersect and except operators in a given XPath query with computed filter expressions. ...

An XPath data binding for a given host language provides a translation of XPath expressions to expressions in the host language. This paper discusses an XPathHaskell data binding. XPath validation ensures that a path addresses a possibly nonempty set of nodes in XML documents described by an XML Schema. We present a generic function (defined by induction on the type structure) that validates XP...

XML is becoming the de facto standard for information exchange. XML querying is a key component for structured information processing and plays a central role in the next generation world wide web, information management systems and databases. Applications relying on XML processing notably depend on XPath, the standard language for adressing parts of XML documents. Besides its fundamental funct...

We have recently designed a fuzzy extension of the XPath language which provides ranked answers to flexible queries taking profit of fuzzy variants of and, or and avg operators for XPath conditions, as well as two structural constraints, called down and deep, for which a certain degree of relevance is associated. In this work, we describe how to implement the proposed fuzzy XPath with the XQuer...

XPath is a standard for specifying parts of XML documents and a suitable language for both query processing and access control of XML. In this paper, we use the XPath expression for representing user queries and access control for XML. And we propose an access-control method for XML, where we control accesses to XML documents by filtering query XPath expressions through access-control XPath exp...

XPath expressions play a central role in querying for XML fragments. We present a containment test of two XPath queries which checks whether a new XPath query XP1 can reuse a previous query result XP2. The key idea is to transform XP1 into a graph which is used to search for sequences of elements which are used in the XPath query XP2.

XPath is a language for addressing fragments of XML documents, used in query and transformation languages such as XQuery and XSLT. For many applications it is desirable to process XPath on the fly and progressively against data streams. This diploma thesis is devoted to streamed and progressive evaluation of XPath. A streamed and progressive XPath evaluation considerably reduces the needed memo...