Change Global Preferences for WF Notification Style

I come across with one of such requirement where I have to change the Global Preference from Backend. Here how I did it

Changing Global preferences for notification style
=====================================================
select PREFERENCE_VALUE
from FND_USER_PREFERENCES
where USER_NAME='-WF_DEFAULT-'
and MODULE_NAME='WF'
and PREFERENCE_NAME='MAILTYPE' ;

Now Update the record :

Update FND_USER_PREFERENCES
set PREFERENCE_VALUE = 'MAILATTH'
where USER_NAME='-WF_DEFAULT-'
and MODULE_NAME='WF'
and PREFERENCE_NAME='MAILTYPE' ;

Different PREFERENCE_VALUES to select from
====================================
MAILATTH == Plain text with HTML attachment
MAILTEXT == Plain Text
SUMMARY == Plain text Summary email
MAILHTML == HTML Mail with attachments
MAILHTM2 == HTML Mail
SUMHTML == HTML Summary email

Happy Troubleshooting !!!