Technical Report 149,
Institut für Informatik,
XPath-Logic and XPathLog: A Logic-Based Approach for
Declarative XML Data Manipulation
In this work, a logic-based framework for handling XML data is
proposed. XPath-Logic embeds an extension of the XPath query
language into first-order logic. We give a model-theoretic semantics
of XPath-Logic formulas based on answer-sets. XPathLog is the Horn
fragment of XPath-Logic, providing a logic-based language for
manipulating and integrating XML data. Due to the close
relationship with XPath, the semantics of rules is easy to grasp. In
contrast to other approaches, the XPath syntax and semantics is also
used for a declarative specification how the database should be
updated: when used in rule heads, XPath filters are
interpreted as specifications of elements and properties which
should be added to the database. The formal semantics is defined
wrt. a Herbrand structure which covers the XML data model.
XPathLog has been implemented in
Revised versions can be found in the
Habilitation Thesis and in
Theory and Practice of Logic Programming, 2004.
Further documentation can be found on the
LoPiX project homepage.