PHP中的SUM运算符无法显示结果[关闭]

Question

may I ask for help? I cannot show out the result. If I run the code without the SUM operator, it works properly. Please help, thank you very much.

     $sql1 ="SELECT SUM(SeatAmount) FROM reservation 
             WHERE RsvDate BETWEEN '07/01/2013' AND '07/31/2013'";

     $result1 = $con->query($sql1);

    printf('<td>'); 
    printf('<b>Seat Amount</b><br/>'); 
    while ($row1 = $result1->fetch_object())
    {
        printf('

          %d<br/>',$row1->SeatAmount);
    }

Answer 1

$sql1 ="SELECT SUM(SeatAmount) AS Total FROM reservation 
         WHERE RsvDate BETWEEN '07/01/2013' AND '07/31/2013'";

 $result1 = $con->query($sql1);

printf('<td>'); 
printf('<b>Seat Amount</b><br/>'); 
while ($row1 = $result1->fetch_object())
{
    printf('

      %d<br/>',$row1->Total);
}