How to imcrement numbers automatically in a FC's atrribute table?

Question

Hi 
I have a FC in personal GDB and SDE GDB.
Is there any way I can have a number automatically incremented in a field, but this number should be always incremented even between different editing sessions. E.g.
session 1:
Starts with 100
for each feature added the number goes +1 in the field automatically.100 features added.
Session 2
Starts with 200 and keeps growing by 1.

Any solution for PGDB or SDE GDB welcomed

VaL · Answer

If you are working with some flavor of SDE, you can create a trigger that gets pulled when the delta table gets updated; this trigger updates the field.  With incremental numbers it gets a little tricky, but I've seen posts that discuss it.

I do have SDE on Oracle.
I have investigated this option as it seems logical.
The problem is that when one want to edit a FC in SDE the FC must be registered as versioned. 
From this moment on there are two delta tables that are created and the new features are added/deleted in the addition/deletion tables. 
It is not in the original FC's table so this makes implementing triggers tricky if at all possible. Actually Oracle doesnt see the new features in the original FC, and SDE sees the in it but actually they are in the delta tables.
Could you point me to these posts?
Thanks

JoeBorgione · Answer

If you are working with some flavor of SDE, you can create a trigger that gets pulled when the delta table gets updated; this trigger updates the field.  With incremental numbers it gets a little tricky, but I've seen posts that discuss it.

VaL · Answer

Isn't that what the ObjectID attribute does? Or do you want the unique attribute to be within a specified range?

Yes, this is what ObjectID does. But I need it to be done for another field in the same automated way at the time of adding a feature to the FC.
It would be good to be in a specified range but it will do even if it is from 1.