Model 204

Model 204 is a Database management system for IBM and compatible mainframes, which was first deployed in 1972. It incorporates a programming language and an environment for application development. It can deal with very large databases and very high transaction loads.^{[citation needed]}

Model 204 relies on its own type of bitmap index, originally devised by Professor Patrick E. O'Neil, and also combines the use of hash table, B-tree, and record list technologies to optimize speed and efficiency of database access.^[1][2]

Model 204 is most commonly used in government and military applications.^{[citation needed]} Among other things, it runs Australia's social security system (Centrelink).^{[citation needed]} It is used commercially in the UK by Marks & Spencer.^{[citation needed]} It is also used at the Ventura County Property Tax system in California,^{[citation needed]} and in the New York City Department of Education's Automate The Schools system.

It is a product of Computer Corporation of America (CCA). In April 2010, CCA was acquired by Rocket Software, a Boston-based developer of Enterprise Infrastructure products.^[3]

Add-on products are available from Sirius Software, Inc.

Database Programmer's Toolkit is a freeware PC-based emulation.

See also

• Entity-attribute-value model

References

1. ^ O'Neil, Patrick (1987). "Model 204 Architecture and Performance". Proceedings of the 2nd International Workshop on High Performance Transaction Systems. Springer-Verlag. pp. 40–59. http://portal.acm.org/citation.cfm?coll=GUIDE&dl=GUIDE&id=658338. 
2. ^ Sandy Stanhope, Database Administrator. "What is Model 204?". The Youngstown State University Computing Newsletter. Department of Computer Services. http://cc.ysu.edu/ComputerServices/Newsletter/link0102/model204.htm. Retrieved 11 January 2008. 
3. ^ http://www.ebizq.net/news/12526.html; acquired June 13, 2010

External links

• Model 204 at Rocket Software
• Model 204 at Sirius Software
• An example of Model 204 User Language programming