Toad World® Forums

Relationship Arc's



Is it possible with Toad Data Modeler to create relationship arc’s (exclusive or-relationships) in the logical model?



Hi Mike,

Arc’s are not available in TDM. However, in TDM LER model you can create exclusive inheritances.

Double-click an inheritance | General tab | select the Exclusive checkbox.

I hope this will help.


Vladka + TDM Team


Thanks for your answer.

Unfortunately I can’t use this feature to design the following case:

A type has zero to many values.
A Item has zero to many values.
A Value relates eighter to a type or a item but never to both of them.

   **TYPE**                 **ITEM**          \                      /
       \                    /
        \                  /
           \             /
            A          A

**How can I logically model this case using the TOAD Data Modeler, and generate the technical model out of the logical model?


Just so you know (not trying to say you don’t need it), but arc’s are a non-standard modeling construct that Oracle Designer and the Barker Notation introduced. Also, Oracle Designer allows arc’s on both sides of the relationships - which make some scenario very difficult to have the database enforce either through constraints and/or triggers.

But I’ve asked for it before of the team - so maybe the product manager will ring in and get this for some future release. We could add arc support inside our current notations - so who knows :slight_smile:



Thanks for your answer!

I will also send a feature request to the quest - data modeler developer team.


No need - I am on the team. I work for Quest and help design what features go into our products (architect?) …