STUFF command in SQL Server

This command is used to replace a string with another string within a text. This command can sometimes be a savior. You can see the shape of this command along with the example:

Syntax:

STUFF ( character_expression1 ,   start ,   length , character_expression2 )

Example:

 SELECT STUFF( SQL SERVER is USEFUL' , 5 , 6 , 'DATABASE')

Output:

SQL DATABASE is USEFUL