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User-Defined Aggregates in Database Languages
This work was done by Punit Bhargava as Master's thesis under the guidance of
Dr. Carlo Zaniolo. The postcript version of the thesis can be downloaded from
here .
Any comments or suggestions could be mailed to
punit@cs.ucla.edu.
Abstract:
Applications, such as OLAP, data warehousing, and data mining, are steering
today's database industry. These applications process highly complex queries
and make extensive use of complex aggregates such as online aggregation and
data cubing.
Current SQL2 compliant database systems cannot support these complex
aggregates. In fact, SQL2 only supports five aggregates and provides no
mechanism for defining new aggregates. Constructs for specifying new aggregates
(i.e., user defined aggregates) are part of the forthcoming SQL3 standards.
In this thesis, we propose SQL-AG, a language and a system to support
user-defined aggregate in SQL. The proposal extends SQL3 user-defined
aggregates and removes some of their limitations to allow the definition of
on-line aggregates, data cubes and other aggregates used in data mining.
This report describes the design and implementation of the SQL-AG system. We
begin with an introduction to the problem, followed by an analysis
of the design issues related to SQL-AG. All details of the design and
implementation of SQL-AG, along with a discussion of the implementation
environment based on Oracle Corporation's server and PL/SQL, are presented.
Punit Bhargava
Wed Mar 11 18:50:53 PST 1998
All contents copyright © 1998, Punit Bhargava.