Toad World® Forums

Hidden inheritance problem


Try this:


Create two entities.
Crete inheritance relationship between them.
Now the inheritance with normal delete.

Then try to recreate it once again. It seems OK.

Remove it again.

And now try to create inverse inheritance between those entities.
The inheritance will blink and disappear.

It cannot be created, because there already exists at least one inverse (hidden) inheritance.

If it can’t be done because of this, some hint or message box would be nice to explain the situation.

Experienced user can use COMPLETE ALL and delete the old one.

When you completely delete the old inheritance, new inverse inheritance can be made without any problem.


Hello arki,

To be honest, I’m not quite sure why you remove shortcuts of inheritances and then create new ones.
It seems the root of the problem is using Del instead of Shift + Del.

I do believe TDM3 users will get used to using Del to remove shortcuts and SHIFT+Del to delete objects. No hint or message box will be necessary.

Similar topic has been discussed about relationships - please see the following thread:

If you have any remarks, please write me back. Thanks.



Maybe I was misunderstood.
It’s not a problem of DELETE or shift+delete.

The problem is in inability to create inheritance.

There is no such problem when creating other relationship types, only for inheritance in LER. Other types of relationship can be added multiple times.

You drag… move , drop and nothing happens. It vanishes.

I may not be the only one that is working with model.

In some programs, these situations are handled with ONE TIME warning dialog boxes that discusess it: “You can’t add it, because, Look for … in model explorer,… Try to, and this.” There is one check box, if you check it no warning will be displayed in future for this situation.


Hello arki,

It’s not a problem of DELETE or shift+delete. The problem is in inability to create inheritance.

Thanks for your reply.

What I guess the problem is:
An inheritance exists (its shortcut has only been removed). TDM3 allows you to add another inheritance - from entity A to entity B, but not from entity B to entity A. You think it would be fine to add a hint or message box to advise the user that it’s necessary to delete the old inheritance.
Am I right?

If I still misunderstand…

Let me try to imagine the situation:
I create inheritance.
a] I find it’s not correct, so I need to delete it. I press SHIFT+Del. When I create a new one, everything should be O.K.

b] I remove it as I do not want to see it in this WS (possibly) and add another inheritance. Same entities with two inheritances. - Can you please give me an example of this use? Why would I need this?

c] I remove it and would like to create inverse inheritance. - Again, can you please give me an example of using inverse inheritance?

To sum up:

  1. Why will I create two inheritances between two same entities?
  2. Why will I create inheritance and inverse inheritance between entities?

Thanks very much for your explanation. I’m sure it will help me understand better.


Vladka + TDM Team


Hi again,

  1. I create inheritance from entity A to B.
  2. I find I need it from entity B to A and press Delete instead of SHIFT+Del (I’m a new user or simply forget that SHIFT has to be used.)
  3. When I try to add a new inheritance from entity B to A, it’s not possible.

-> How we will fix it: A message will appear in Message Explorer. Something like: An inheritance already exists. First, you need to delete the inheritance from your model.

  • CR # 37 082.