Question

please tell me a good tutorial to learn
php mysql
login with facebook

Does login with facebook use the facebook api or the facebook sdk.

Answer 1

use this TUTORIAL

There is one problem with his config.php file.Rather than using if(is_null($facebook->getUser()))... use following code for checking if user already exists.

try{
    $me = $facebook->api('/me');
$error='no';
    }
    catch (FacebookApiException $e) {
        $error='yes';
        $perms=array('req_perms' => 'user_status,publish_stream,user_photos,email,status_update,friends_status,export_stream');
        echo"<meta http-equiv='refresh' content='0; URL=".$facebook->getLoginUrl($perms,$cancel,$next,$display)."'>";
        exit;           
      }
    if($error!='yes'){//already logged in use normally
            }