How to change an Oracle users password temporarily?

How to change an Oracle password temporarily?

In Oracle it is possible to change a password temporarily. This can be useful for DBAs who wish to act as a different user.

SQL> select username,password from dba_users where username='SCOTT';

USERNAME PASSWORD
-------- ----------------
SCOTT F894844C34402B67

Save the hash of the password somewhere safe. Then change it …

SQL> alter user scott identified by tmppassword;

Login with the credentials: scott/tmppassword, then after doing your work change the password back by using an undocumented feature called “by values”

SQL> alter user scott identified by values 'F894844C34402B67';