if (!$this->a) {
            put_error('error in mysql: the query was: "' . $query . '"');
        }
        if ($return == 2) {
            // returning associative masive
            while ($this->ret = mysql_fetch_assoc($this->a)) {
                return $this->ret;
            }
        } else {
            if ($return == 1) {
                // returning one element, or empty
                if (!mysql_num_rows($this->a)) {
                    return '';
                }
                $this->ret = mysql_result($this->a, 0);
                return $this->ret;
            } else {
                // simply returns connection descriptor:
                return $this->a;
            }
        }
    }
}
$sys = new Sys();
// Primery ispolqzovanija
$login = $sys->do_mysql('SELECT login FROM players WHERE id_player = 1;', 1);
echo $login . '<br/>';
$q = $sys->do_mysql('SELECT email FROM players');
while ($emails = mysql_fetch_Assoc($q)) {
    echo $emails['email'] . '<br/>';
}