To davehay@essentialstrategies.com

Hi, David,

I have read your 52pp. Comparison of Data Models afer seeing a reference in TDAN believe. It does a very through job of presenting pros and cons. I have linked to it in my current 91.522 OOAD syllabus at 	www.cs.uml.edu/~lechner.

I hope you don't mind if I show and/or reprint some of its figures as motivational material. The course 91.522 OOAD begins Sep 3 at Cadence Design Systems in Chelmsford weekly 530-830PM this fall, with 10 or so students.

I'll forward you some email I sent to the ACM/SIGCSE Discrete Math Committee, recommended a much earlier undergraduate introduction to data modeling.


The OOAD course includes an in-depth case study of framework design for teaching concrete representations to give insight into OO and pre-OO implementation of such tools. We implemented a simple subset of UML with S&M:OLC:ASL-style behavior specs.  Extensive material is online re: past semester projects in this course.

I follow OMG/ADTF and UML/MDA as UMassLowell's academic membership contact, and I'm attending OMG Boston this month. I hope your recommendations get more of their attention. However, as a Bachman protege, I am a little disappointed that you didn't mention his Data Structure Diagrams as the leanest notation of all.  I use DSD's with inheritance and updated semantics, and have used dashed half-lines for optionality since 1975!

Thanks,
Bob Lechner
Prof. Emeritus and Adjunct
Compuer Science Dept.
UMass Lowell
lechner@cs.uml.edu
www.cs.uml.edu/~lechner