public function getUCsNumberByAreaId($id){
        $db = new DB();
        $db->dbConnect();
        $ucs = array();
        $i = 0;
        $sql = "SELECT uc.nome FROM uc, area
        WHERE uc.id_area = area.id
        AND area.id = ".$id.";";
        $result = mysqli_query($db->con, $sql);
        $db->dbClose();
        if ($result->num_rows > 0) {
            while($row = mysqli_fetch_array($result)) {
                $ucs[$i]["nome"] = $row['nome'];
                $i++;
            }
            return $i;
        } else {
            return '0';
        }
    }