concatenation operator or just single quotes?

[V]

I'm trying to decide which is better or if there is any significant difference between the two. Both are within function brackets and they seem to work either way. 

 

$result = $conn->query("update user
                          set passwd = sha1('".$new_password."')
                          where username = '".$username."'");


$result = $conn->query("update user
                          set passwd = sha1('$new_password')
                          where username = '$username'");

[Pikachu2000]

Echo them both, and see if they produce the same string. If they do, go with the simplest variation.

[V]

Thanks! They both work  so I'll just go with the simple one