duplicate dba_users

[stecal]

I can see this happening:

SQL> create user "Scott" identified by tiger;

User created.

SQL> select username from dba_users
  2  where username like 'S%';

USERNAME
---------
SCOTT
SYS
SYSTEM
Scott

Try select username, user_id from dba_users;

The lower numbers for sys and system (probably like 0 and 5) are the "real" sys and system users.

Aside from the user_id, there is something else different between users whose names appear to be the same.