Re: Chen-ERD and Crow's Foot Diagrams?

[Andrew S Halper <ashalper acm org>]

On 2002.04.06 02:47 Cyrille Chepelov wrote:
> Le Sat, Apr 06, 2002, à 08:18:10AM +0200, Daryl Manning a écrit:

> > Just seemed like a fast easy way to support Crow's Feet and it is
> what
> > they happen to do in Visio anyway?
> 
> 
> I'm lost. What are crow's feet diagrams ? Can you give me a pointer ?

Information Engineering (a.k.a.: Crow's Feet, IE, Information 
Engineering Methodology, IEM) and IDEF (especially IDEF1X) are common 
standards for ER diagrams.  I think Visio supports IE (I've never used 
Visio), ERwin supports IE and IDEF1X (and possibly UML in later 
versions I think).  ER/Studio supports IDEF1X and possibly others.

An example of IE is on page 12 of this rather large PDF file:

http://tor.utdallas.edu/mis6326sp2k2/notes/visiopro2000.pdf

An example of IDEF1X is on pages 26-28 of this PDF file:

http://www.idef.com/Downloads/pdf/Idef1x.pdf

In fact this is the entire IDEF1X standard.

Although they have varying degrees of expressiveness, traditional ER 
(like Dia uses), Chen, IE, IDEF1X, and UML-as-ER (like I used in the 
SQL plug-in), are just different notations for representing the same 
underlying ER model, which is why I suggested they be unified under 
another application.  It could be done by Dia, but it would involve 
some radical surgery of the ER and UML code, and I don't know if it's 
worth the risk of dinging up these two imporant features.

Andy