[om-list] use cases: create/edit/delete relationship

[Luke Call]

[These need work too.]

*****create relationship (these are for users; internally is much the 
same; as per 9/15/2000 email from mbutler, which said: "For user 
interface purposes, we should add separate use cases for "create
relationship", "edit relationship", "move relationship", and "delete
relationship".
Internally, a property and a relationship are actually the same thing, but
making the distinction on the user interface level makes life much 
easier for
users who do not want to consider that abstractions like "height", "weight",
and "color" are relationships to or between full blown entities. 
Traditional
data modelling makes a distinction between the latter, which is called a
"domain" and the former, which is called an "entity".

 From a user interface point of view, you need to have the two entities 
ahead
of time to create a relationship (e.g. by connecting them together with a
relationship tool and two mouse clicks), but when you add a property, 
the true
domain or counterpart entity of the property may be left undefined until
later.  When we have a graphical interface, we need a way to view only 
include
the entities and relationships we care about, because otherwise the 
resulting
network can be a nightmare to comprehend.

By the way, when I said text user interface, I meant a command line 
interface
for low level testing purposes.  If we are going to build a real user
interface, it should be graphical. ")
*****edit relationship
*****delete relationship


[end]