[Colloquium] Reminder: today's talk by Ashraf Aboulnaga, IBM Almaden

[Margery Ishmael]

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DEPARTMENT OF COMPUTER SCIENCE

Date: Friday, March 5, 2004
Time: 2:30 p.m.
Place: Ryerson 251

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Speaker:  ASHRAF ABOULNAGA, IBM Almaden Research Center

Url:  http://www.cs.wisc.edu/~ashraf/

Title:  On-line Statistics for Database Query Optimization

Abstract:

Database system query optimizers rely on statistics about the data in a
database to estimate the cost of different query execution plans and 
choose
the best plan to execute a user query. These database statistics are
traditionally built by reading the data and summarizing its 
characteristics
in a small amount of memory. In this talk, I will present a novel 
approach
to building database statistics in an on-line manner, not by reading the
data, but rather by observing user queries over the data and their 
result
sizes and using this feedback information to construct the statistics. I
will present self-tuning histograms, which are on-line statistics for
relational data that are particularly useful in the context of 
self-tuning
database systems. I will also present on-line statistics for XML path
expressions in the context of querying hidden web data sources over
the Internet.

Speaker Bio:

Ashraf Aboulnaga obtained a Ph.D. in computer science from the 
University of
Wisconsin - Madison in 2002. He is currently a research staff member in 
the
Data Management Department at the IBM Almaden Research Center in San 
Jose, CA.
His research interests are in the area of data management, with a 
current focus
on advanced query optimization and processing, self-managing database 
systems,
and Internet data management. Ashraf's previous activities include 
working on
the Niagara XML data management project at the University of Wisconsin 
and on
self-tuning database systems at Microsoft Research.

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Host: David BEAZLEY

*Refreshments will follow the talk in Ryerson 255*

People in need of assistance should call 773-834-8977 in advance.