MPhil Thesis Defence


"TEMPLATE-BASED RUNTIME INVALIDATION OF DATABASE-GENERATED WEB CONTENTS"

By

Mr. Chun-Yi Choi


Abstract

Many database-backed web sites deploy web caches to improve response time
and system throughput. Nevertheless, database updates introduce
inconsistency between the cached database-generated web pages and the
corresponding database contents.  This poses the problem of cache
consistency maintenance for database-generated web contents.

This thesis states that template-based invalidation techniques are
feasible and efficient for cache consistency maintenance of
database-generated web pages.  We identify cached web pages and database
operations by parameterized URLs (URL templates) and parameterized SQL
statements (SQL templates).  We then utilize the satisfiability testing
algorithm in the literature to check the relationship between database
queries and database updates.  With the result of this testing and the
correspondence between URL templates and SQL templates, we invalidate
cached web pages as necessary.  Furthermore, we extend the testing
algorithm to handle a common class of queries (possibly with
uninstantiated variables).  In addition, we propose several techniques
including pre-computation, indexing, group invalidation, and polling to
further improve the efficiency and effectiveness of our template-based
invalidation.  We have implemented a template-based invalidator (TBI)
using typical database-backed web site software and have conducted
extensive experiments using representative benchmarks.  Our experimental
results clearly demonstrate the feasibility and efficiency of our
template-based invalidation techniques.


Date:				Saturday, 21 August 2004

Time:				10:00a.m.-12:00noon

Venue:				Room 2406
				Lifts 17-18

Committee Members:		Prof. Qiong Luo (Supervisor)
				Prof. Shing-Chi Cheung (Chairperson)
				Prof. Hongjun Lu


**** ALL are Welcome ****