php - 显示数据库值的总和 - PHP

Question

嗨，我需要获取数据库字段 sbstart 的总和。我将代码更改为 SUM(sbstart) 但似乎不是一个有效的举措。如何显示总和？谢谢。

        <?php


$host = 'localhost';
$user = 'root';
$pass = '';
$db = 'regional_data';
@ $db = mysqli_connect($host, $user, $pass, $db);

if(mysqli_connect_errno())
{
    die('The connection to the database could not be established.');
}
$query = "SELECT SUM(sbstart) FROM newchk WHERE dist_chk ='$distUsr'";
$result = mysqli_query($db, $query);

while ($recS = mysqli_fetch_array($result)){

echo ($recS['sbstart']);    
}
?>

Answer 1

改变

$query = "SELECT SUM(sbstart) FROM newchk WHERE dist_chk ='$distUsr'";

至（使用别名）

$query = "SELECT SUM(sbstart) as sub FROM newchk WHERE dist_chk ='$distUsr'";

然后

you doesn't need while loop because it return only one result.

$recS = mysqli_fetch_array($result);
echo $recS['sub'];

Answer 2

您需要使用其中一个mysqli_fetch_assoc来代替mysql_fetch_array，或者您需要使用echo $recS[0].

Answer 3

改变

$query = "SELECT SUM(sbstart) FROM newchk WHERE dist_chk ='$distUsr'";

到

$query = "SELECT SUM(sbstart) AS sum FROM newchk WHERE dist_chk ='$distUsr'";

和改变

echo ($recS['sbstart']);

到

echo ($recS['sum']);