Personal Views for Web Catalogs
H. Su,
D. Kramer,
L. Chen,
K. Claypool,
E. Rundensteiner
Eleventh International Workshop on Research Issues in Data
Engineering, Heidelberg, Germany, Apr. 1-2, 2001, pp. 103--110
As information on the world wide web continues to proliferate at an
astounding rate, the extensible markup language (XML) has been
emerging as a standard format for data representation on the web. In
many applications, specific document type definitions (DTDs) are
designed to enforce a semantically agreed-upon structure of the XML
documents for management. However, both the data and the structure of
XML documents tend to change over time for a multitude of reasons,
including to correct design errors in the DTD, to allow expansion of
the application scope over time, or to account for the merging of
several businesses into one. However, most of the current software
tools that enable the use of XML do not provide explicit support for
such data or schema changes. In this vein, we put forth the first
solution framework, called XML Evolution Manager (XEM) to manage the
evolution of XML. XEM provides a minimal yet complete taxonomy of
basic change primitives. These primitives, classified as either data
changes or schema changes, are consistency-preserving, i.e., (1) for a
data change, they ensure that the modified XML document conforms to
its DTD both in structure and constraints; and (2) for a schema
change, they ensure that the new DTD is a valid DTD and all existing
XML documents are transformed also to conform to the modified DTD. We
prove the completeness of the taxonomy in terms of DTD
transformation. To verify the feasibility of our XEM approach we have
implemented a working prototype system using PSE Pro as our backend
storage system.
Download: