PHP unique sessions

Hi how do I use a unique hash for session's ? like when I do an 开发者_如何学Cif statement :

if ($_SESSION['BOOTY'] != 0){ 
 echo Nice $_SESSION['BOOTY'];
}

it wont work. How to do a comparison of unique hashes with an if statement ?

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you can try using isset() method instead of equating to zero ...

if(isset($_SESSION['booty']))