我需要閱讀一張代表每月登記的表格。有點像year, month, name, d1...d31 <--days of the month我使用這個函數(shù)來獲取當月的全球小時數(shù)function calchour($db, $table, $year, $month){    $daysinmonth =cal_days_in_month(CAL_GREGORIAN, $month, $year);//Nbr of days in month    $tt_hour = '0';    $result = mysqli_query($db,"SELECT * FROM $table WHERE anno = '$year' AND month = '$month'") or merror($msg = mysqli_error($db));      while ($row = mysqli_fetch_array($result))    {        $volhr = '0';        for ($i = '1'; $i <= $daysinmonth; $i++) {            $day = 'd'.$i;            $hour = $row[$day];            if (($hour != '')) { $volhr = $volhr + $hour; }        }        $tt_hour = $tt_hour + $volhr;    }return $tt_hour;    }有沒有更好的方法來獲取當月的全球小時數(shù)？