Optimization of Complex Queries in a Database Management System

Supported by the Centre for Advanced Studies at the IBM Toronto Laboratory
and UMD Research

Principal Investigator

Dr. Qiang Zhu
Department of Computer and Information Science,
The University of Michigan - Dearborn, MI 48128
qzhu@umich.edu

Industrial Collaborators

Calisto Zuzarte & Berni Schiefer
Database Technology
IBM Toronto Laboratory

Graduate Students

Yingying Tao, IBM CAS fellowship student

Project Overview

As database technology is applied to more and more application areas, user queries become more and more complex in terms of the following three dimensions: (1) the number of operations (e.g., 50-100 joins), (2) the degree of heterogeneity of operations (e.g., regular joins, spatial joins and user-defined operations), and (3) the types of interactions among operations (e.g., queries with star-schema structures and queries with clustered interactions in their query graphs). The query optimization techniques adopted in the existing database management systems have not caught up with the demanding growth of query complexity from applications and cannot cope with this new challenge well. The main goal of this project is to investigate some efficient techniques to optimize such complex queries.

Project References

Qiang Zhu, Yingying Tao and Calisto Zuzarte, Optimizing Complex Queries Based on Similarities of Subqueries, Knowledge and Information Systems: an International Journal, Vol. 8, No. 3, pp 350-373, 2005.

Yingying Tao, Qiang Zhu, Calisto Zuzarte and Wing Lau, Optimizing Star-Schema Queries with Snowflakes via Heuristic-Based Query Rewriting, Proceedings of CASCON'03, pp 261 - 275, 2003.

Yingying Tao, Qiang Zhu and Calisto Zuzarte, Exploiting Similarity of Subqueries for Complex Query Optimization, Proc. of 14th International Conference on Database and Expert Systems Applications (DEXA'03), LNCS, Vol. 2736, pp 747 - 759, 2003.

Yingying Tao, Qiang Zhu and Calisto Zuzarte, Exploiting Common Sunqueries for Complex Query Optimization, Proceedings of CASCON'02, pp 21 - 34, 2002.