Delete only certain things from database

Question

I got this php script from w3schools and I was wondering if its possible to only delete the last name and leave the first name which is peter?

<?php
$con=mysqli_connect("example.com","peter","abc123","my_db");
// Check connection
if (mysqli_connect_errno())
{
 echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

 mysqli_query($con,"DELETE FROM Persons WHERE LastName='Griffin'");

mysqli_close($con);
?> 

source: http://www.w3schools.com/php/php_mysql_delete.asp

Answer 1

Yes, just do

UPDATE Persons
    set LastName = ''
WHERE
    id = ?

or alternatively set LastName = NULL