CODASYL is remembered almost entirely for two activities: its work on the development of the COBOL language and its activities in standardizing database interfaces. It also worked on a wide range of other topics, including end-user form interfaces and operating-system control languages, but these projects had little lasting impact.
The remainder of this section is concerned with CODASYL's database activities.
In 1965 CODASYL formed a List Processing Task Force. This group was chartered to develop COBOL language extensions for processing collections of records; the name arose because Charles Bachman's IDS system (which was the main technical input to the project) managed relationships between records using chains of pointers. In 1967 the group renamed itself the Data Base Task Group(DBTG), and its first report in January 1968 was entitled COBOL extensions to handle data bases.
In October 1969 the DBTG published its first language specifications for the network database model which became generally known as the Codasyl Data Model. This specification in fact defined several separate languages: a data definition language (DDL) to define the schema of the database, another DDL to create one or more subschemas defining application views of the database; and a data manipulation language (DML) defining verbs for embedding in the COBOL programming language to request and update data in the database. Although the work was focused on COBOL, the idea of a host-language independent database was starting to emerge, prompted by IBM's advocacy of PL/I as a COBOL replacement.
In 1971, largely in response to the need for programming language independence, the work was reorganized: development of the Data Description Language was continued by the Data Description Language Committee, while the COBOL DML was taken over by the COBOL language committee. With hindsight, this split had unfortunate consequences. The two groups never quite managed to synchronize their specifications, leaving vendors to patch up the differences. The inevitable consequence was a lack of interoperability among implementations.
A number of vendors implemented database products conforming (roughly) to the DBTG specifications: the most well-known implementations were Honeywell's Integrated Data Store (IDS/2), Cullinet's Integrated Database Management System IDMS, Univac's DMS-1100, and Digital Equipment Corporation's DBMS32. Cullinet, originally known as Cullinane Database Systems, obtained the technology from B.F. Goodrich. Cullinet was eventually sold to Computer Associates, which as of 2007 still sells and supports a version of IDMS.
ANSI and ISO adopted the Codasyl database specifications under the name Network Database Language (NDL), with work taking place within the same working group (X3H2) as SQL standardization. An ISO standard for NDL was ratified as ISO 8907:1987, but it never had any practical effect on implementations, and was formally withdrawn in 1998.
Some of the CODASYL committees continue their work today, but CODASYL itself no longer exists. The records of CODASYL were donated to the Charles Babbage Institute and a catalog may be found at their website.
Interest in CODASYL gradually faded due to growing interest in relational databases beginning in the early 1980s.
Read more about this topic: CODASYL
Other articles related to "history":
... believed that gambling in some form or another has been seen in almost every society in history ... and Romans to Napoleon's France and Elizabethan England, much of history is filled with stories of entertainment based on games of chance ... In American history, early gambling establishments were known as saloons ...
... History of Charles XII, King of Sweden (1731) The Age of Louis XIV (1751) The Age of Louis XV (1746–1752) Annals of the Empire – Charlemagne, A.D ... Essay on the Manners of Nations (or 'Universal History') (1756) History of the Russian Empire Under Peter the Great (Vol ... II 1763) History of the Parliament of Paris (1769) ...
... The history of computing is longer than the history of computing hardware and modern computing technology and includes the history of methods intended for pen and paper or for chalk and slate ...
... The Skeptical School of early Chinese history, started by Gu Jiegang in the 1920s, was the first group of scholars within China to seriously question the ... early Chinese history is a tale told and retold for generations, during which new elements were added to the front end" ...
... The breakup of Al-Andalus into the competing taifa kingdoms helped the long embattled Iberian Christian kingdoms gain the initiative ... The capture of the strategically central city of Toledo in 1085 marked a significant shift in the balance of power in favour of the Christian kingdoms ...
Famous quotes containing the word history:
“The reverence for the Scriptures is an element of civilization, for thus has the history of the world been preserved, and is preserved.”
—Ralph Waldo Emerson (18031882)
“The history of the genesis or the old mythology repeats itself in the experience of every child. He too is a demon or god thrown into a particular chaos, where he strives ever to lead things from disorder into order.”
—Ralph Waldo Emerson (18031882)
“It is true that this man was nothing but an elemental force in motion, directed and rendered more effective by extreme cunning and by a relentless tactical clairvoyance .... Hitler was history in its purest form.”
—Albert Camus (19131960)