用Facebook api更新mysql

i've got a mysql server in wich i want to save all the events that some pages creates. i know how to put the data in mysql table but i don't know why it doesn't work,

it says: Fatal error: Class 'FacebookRequest' not found in /membri/bestparty/IOS/Prova.php on line 3

here is the sample code

<?

$request = new FacebookRequest(
  $session,
  'GET',
  '/{1389372264700040}/picture'
);

echo "$picture";

/* handle the result */


?>

it should work.. i want to save some details about the events, in the code above i'm only trying to print the variable to know if it works.

where use or inclure|include? like:

use Facebook\FacebookRequest;
use Facebook\GraphUser;
use Facebook\FacebookRequestException;

Read all documentations : https://developers.facebook.com/docs/php/gettingstarted/4.0.0

or test that :

<img src="//graph.facebook.com/1389372264700040/picture" />