Whilst the account name (user_name) has to be unique which is enforced by the fnd_user_u2 index, the internal application key is based on the account ID (user_id) not the name
So why would you change an account name?
- A name change by deed poll or marriage
- A new employee has the same name as an ex-employee
- The user name was entered incorrectly
- You want to implement a user naming standard
Of course you will need to get this approach signed off by Oracle support and internal audit first. Usually, as long as there is consistent documented evidence of the change audit are generally ok
You are not doing anything dodgy here, this is all done via the standard Oracle application screens (Security > User > Define) just select the user, change the users name and commit.
Note: If you change the name of an active account, you will need to reset that user's password and let them know the password you have set and that they will be required to change their password on first connecting with the new name.
Of course you wouldn’t even attempt to do this without checking with Oracle support and you’re your audit team before changing application user names and then testing, testing etc…..