oconnorp@ul.ie (06/22/91)
Hello to everybody on the Net,
I am currently doing my MSc and have to describe some existing
computer systems using certain diagrams, one of which being the Entitiy-
Relationship diagrams.
My problem is trying to find a good diagramming tool that (in the case
of E-R diagrams) would represents the following information :
Entities possibly represented by rounded rectangles,
Relationships possibly represented by elongated ellipses (optional),
1:m and M:M represented by Crows feet,
Nesting within entities,
Entity Dependency,
Labelling within the Entity and the Relationship Symbols.
The system would have to cater for the usual diagramming facilities
provided by most systems such as scaling and dragging. The systems
Oracle Case and Information Engineering Facility provide the facilities
I require, but at a high price tag.
I have looked at various packages both on DOS machines (Excelerator
and Design Aid) and Ultrix/X-Window/Sunview (Xfig, Graphed) and
have not found a satisfactory diagramming tool.
I am appealing to anybody out there, if they know of any software
(Commercial, Public Domain or Shareware) that can be used on Dos machines
or Ultrix/X-Windows or Sunview machines (prefarably the last type) that
would provide the facilities I require to email me and let me know.
I am including some examples of what I am looking for (using crude
ASCII characters) to give you an idea of what I am doing.
:------: :------:
: :\ ---------------- : :
:Entity:---------( relationship 1 )---------------:Entity:
: A :/ ---------------- : B :
: : :------:
:------:
:-----------------:
:Entity C :--------- and so on....
: :
: :----------: :
: :Nested :----+-------- and so on .....
: : : :
: :----------: :
: :
:-----------------:
--------------------------------------------------------------------------
Paul O' Connor oconnorp@ul.ie
Computer Sciences & Information Systems,
University of Limerick,
Ireland.