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From: Galaxy��VOLUNTEERS��Database
Date: Fri, 16 Jan 2009 13:30
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Edgar Frank "Ted" Codd (August 23, 1923 �C April 18, 2003) was a British 
computer scientist who, while working for IBM, invented the relational 
model for database management, the theoretical basis for relational 
databases. He made other valuable contributions to computer science, but 
the relational model, a very influential general theory of data management, 
remains his most memorable achievement.

Contents [hide]
1 Biography
2 Work
3 See also
4 Publications
5 References
6 Further reading
 

[edit] Biography
Edgar Frank Codd was born on the Isle of Portland, in England. After 
attending Poole Grammar School, he studied mathematics and chemistry at 
Exeter College, Oxford, before serving as a pilot in the Royal Air Force 
during the Second World War. In 1948, he moved to New York to work for IBM 
as a mathematical programmer. In 1953, angered by Senator Joseph McCarthy, 
Codd moved to Ottawa, Canada. A decade later he returned to the U.S. and 
received his doctorate in computer science from the University of Michigan 
in Ann Arbor. Two years later he moved to San Jose, California to work at 
IBM's San Jose Research Laboratory, where he continued to work until the 
1980s. During the 1990s, his health deteriorated and he ceased work. [1]

Codd received the Turing Award in 1981 and in 1994 he was inducted as a 
Fellow of the Association for Computing Machinery[2]

Codd died of heart failure at his home in Williams Island, Florida at the 
age of 79 on Friday, April 18, 2003.[3]


[edit] Work
In the 1960s and 1970s he worked out his theories of data arrangement, 
issuing his paper "A Relational Model of Data for Large Shared Data Banks" 
in 1970, after an internal IBM paper one year earlier.[4] To his 
disappointment, IBM proved slow to exploit his suggestions until commercial 
rivals started implementing them.

Initially, IBM refused to implement the relational model in order to 
preserve revenue from IMS/DB. Codd then showed IBM customers the potential 
of the implementation of its model, and they in turn pressured IBM. Then 
IBM included in its Future Systems project a System R subproject �� but put 
in charge of it developers who were not thoroughly familiar with Codd's 
ideas, and isolated the team from Codd[citation needed]. As a result, they 
did not use Codd's own Alpha language but created a non-relational one, 
SEQUEL. Even so, SEQUEL was so superior to pre-relational systems that it 
was copied, based on pre-launch papers presented at conferences, by Larry 
Ellison in his Oracle Database, which actually reached market before SQL/DS 
�� due to the then-already proprietary status of the original moniker, 
SEQUEL had been renamed SQL.

Codd continued to develop and extend his relational model, sometimes in 
collaboration with Chris Date. One of the normalized forms, the Boyce-Codd 
normal form, is named after him.

Codd's theorem, a result proven in his seminal work on the relational 
model, equates the expressive power of relational algebra and relational 
calculus (which, in essence, is equivalent to first-order logic).

As the relational model started to become fashionable in the early 1980s, 
Codd fought a sometimes bitter campaign to prevent the term being misused 
by database vendors who had merely added a relational veneer to older 
technology. As part of this campaign, he published his 12 rules to define 
what constituted a relational database. His campaign extended to the SQL 
language, which he regarded as an incorrect implementation of the 
theory[citation needed]. This made his position in IBM increasingly 
difficult, so he left to form his own consulting company with Chris Date 
and others.

Edgar Codd coined the term OLAP and wrote the twelve laws of online 
analytical processing, although these were never truly accepted after it 
came out that his white paper on the subject was paid for by a software 
vendor. His last work, a book named The Relational Model for Database 
Management, version 2, was not so well received[citation needed]. On the 
other hand, his extension of the ideas in the relational model to cover 
database design issues, in his RM/T, have proved important[citation needed] 
. Codd also contributed knowledge in the area of cellular automata.

In 2004, SIGMOD renamed its highest prize, the SIGMOD Innovations Award, in 
his honor.
 
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