If a user forgets his or her password, you can replace the forgotten password using the MODIFY USER statement:
MODIFY USER JDoe AS PASSWORD = mysecret FOR USER;
The example MODIFY USER statement replaces the forgotten password with mysecret, and the FOR USER specification causes the system to reset the value for the global PasswordChgDate parameter in the DBC system table to zero. The zero value then causes the existing password to expire at the next logon.
A non-zero profile value supersedes the corresponding global value.
When the MODIFY USER statement resets the forgotten password to a temporary password, the system does not update the DBC.OldPasswords table or verify the temporary password against password reuse rules.