Select Stuff('Muthu Babu', 1, 3, 'Mad')
Stuff function stuffs the given string at the specified location.
In the above sample Mad is stuffed from 1 to 3 position of Muthu Babu
This makes it to stuff Mad in place of Mut so the result becomes
Select Stuff('Muthu Babu', 1, 1, 'Mad')
Hope this helps.