public static function getActiveSessionsNumber()
 {
     Session::validateSessions();
     $sql = "SELECT COUNT(id) AS activeSessions FROM " . Database::getTableName('sessions');
     $response = Database::getInstance()->sql('getActiveSessions', $sql, '', [], false);
     if (is_array($response) && count($response) > 0) {
         return $response[0]['activeSessions'];
     }
     return 0;
 }