Faculty Advisor

Prof. Michael A. Gennert

Faculty Advisor

Prof. Elke A. Rundensteiner

Faculty Advisor

Prof. George T. Heineman


In recent years XML, the eXtensible Markup Language has become the de-facto standard for publishing and exchanging information on the web and in enterprise data integration systems. Materialized views are often used in information integration systems to present a unified schema for efficient querying of distributed and possibly heterogenous data sources. On similar lines, ACE-XQ, an XQuery based semantic caching system shows the significant performance gains achieved by caching query results (as materialized views) and using these materialized views along with query containment techniques for answering future queries over distributed XML data sources. To keep data in these materialized views of ACE-XQ up-to-date, the view must be maintained i.e. whenever the base data changes, the corresponding cached data in the materialized view must also be updated. This thesis builds on the query containment ideas of ACE-XQ and proposes an efficient approach for self-maintenance of materialized views. Our experimental results illustrate the significant performance improvement achieved by this strategy over view re-computation for a variety of situations.


Worcester Polytechnic Institute

Degree Name



Computer Science

Project Type


Date Accepted





XML, Query Re-Writing, View Maintenance, Query Containment, XML (Document markup language), Cache memory, Database searching, Query languages (Computer science)