Authors:
Ali El bekai
and
Nick Rossiter
Affiliation:
School of Informatics, Northumbria University, United Kingdom
Keyword(s):
XML documents, tree algebra, integration framework
Related
Ontology
Subjects/Areas/Topics:
Coupling and Integrating Heterogeneous Data Sources
;
Databases and Information Systems Integration
;
Enterprise Information Systems
Abstract:
This paper introduces a framework in algebra for processing XML data. We develop a simple algebra, called TA (Tree Algebra), for processing storing and manipulating XML data, modelled as trees. We present assumptions of the framework, describe the input and the output of the algebraic operators, and define the syntax of these operators and their semantics in terms of algorithms. Furthermore we define the relational operators and their semantics in terms of algorithms. Examples show that this framework is flexible to capture queries expressed in the domain specific XML query language. As can be seen the input and output of our algebra is a tree that is the input and output are XML document and the XML documents are defined as trees. We also present algorithms for many of the algebra operators; these algorithms show how the algebra operators such as join, union, complement, project, select, expose and vertex work on nodes of the XML tree or element and attributes of an XML document. De
tailed examples are given.
(More)