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Projects archive / The SQLEDDI environment

Title:The SQLEDDI environment
Authors:Meurig Beynon, Michael Evans, Chris Brown
Funding:Acad - Academic research
Short description:Studying the design and implementation of SQL
EM Technologies:tkeden, %eden, %scout, %eddi, %sqlzero
Keywords:notation, tool, translator, education
empublic references:eddipTruong1996, agentparserBrown2001
EMpress references:
Web site references:
Previous locations:~wmb/public/cs233, Abhir Bhalerao's website

This project provides an extension to the tkeden environment in which it is possible to study the use of SQL in conjunction with EDDI, a definitive notation based on relational algebra, as a relational database query language. The design of EDDI is closely based on that of ISBL (as developed by Todd at IBM Peterlee in 1976). The SQLEDDI environment can be used to demonstrate the flaws in the design of SQL that have been identified by commentators such as Date and Darwen, how these distance it from the underlying relational theory of Codd and introduce problematic issues in implementation. Further details of relevant investigations with the model are given in the worksheets and further documentation cited in the README for the model.

The development of the model originated with the work of Truong in 1996, who first devised and implemented EDDI using an eden pipeline. This was later improved by Ward and Beynon. Brown subsequently introduced an EDDI parser within tkeden to demonstrate the operation of his agent-based parser in 2001. Much of the work on the sqleddi environment was carried out by Evans, who implemented the agent-based parser for SQL, and developed the first prototype for the SQL0 interpreter and SQL-to-EDDI translator. The current version of the environment was developed by Beynon in conjunction with a module on Database Systems in October and November 2001. [WMB]

sqleddiBeynon2001 is available locally within DCS at /dcs/emp/empublic/projects/sqleddiBeynon2001
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BeyondSQL0.ppt 53760 03:43 PM Nov 23 2001 01:19 PM Jul 27 2017
README 1244 07:42 PM Sep 04 2002 01:19 PM Jul 27 2017
README.xml 2256 04:26 PM Feb 15 2004 01:19 PM Jul 27 2017
README.xml~ 2256 08:19 PM Sep 04 2002 01:19 PM Jul 27 2017
answerwk5.html 13095 08:09 AM Nov 23 2001 01:19 PM Jul 27 2017
answerwk6.html 10304 02:54 PM Nov 30 2001 01:19 PM Jul 27 2017
screenshot.gif 21357 07:46 PM Sep 04 2002 01:19 PM Jul 27 2017
worksheet5.html 12619 02:52 PM Nov 30 2001 01:19 PM Jul 27 2017
worksheet6.html 13239 02:56 PM Nov 30 2001 01:19 PM Jul 27 2017
development.archive/ 4096 05:27 PM Sep 03 2002 01:19 PM Jul 27 2017
sqleddi/ 4096 08:43 PM Oct 17 2002 01:19 PM Jul 27 2017

empublic system initially created by Ashley Ward with assistance from Chris Roe and Meurig Beynon.