从特定行获取求和值

Question

我有这个：

$result = mysqli_query($mysqli, "SELECT balance FROM " . MYSQLBTCTABLE . " WHERE address='" . $_POST['address'] . "' LIMIT 1");
while($row = mysqli_fetch_assoc($result)) {
    $balance = $row['balance'];

echo "<font style='font-weight:bold;'>Your current balance is: </font><br/>";
printf("%0.8f", ($balance / 100000000));

但它只获取我需要的最后一个值来查找该地址的所有余额，并将$balance的总和相加。

Answer 1

使用

$balance += $row['balance'];

Answer 2

使用agregation：

$result = mysqli_query($mysqli, "SELECT sum(balance) FROM " . MYSQLBTCTABLE . " WHERE address='" . $_POST['address'] . "' GROUP BY address");

Answer 3

从查询中删除LIMIT并添加SUM

$result = mysqli_query($mysqli, "SELECT SUM(balance) as totalBalance FROM " . MYSQLBTCTABLE . " WHERE address='" . $_POST['address'] . "'");
$row = mysqli_fetch_assoc($result);
$balance = $row['totalBalance'];

echo "<font style='font-weight:bold;'>Your current balance is: </font><br/>";
printf("%0.8f", ($balance / 100000000));

Answer 4

首先，改为：

$balance = $row['balance'];

使用：

$balance += $row['balance'];

此外，摆脱“LIMIT 1”约束

Answer 5

Remove limit 1 and do the sum

        $result = mysqli_query($mysqli, "SELECT balance FROM " . MYSQLBTCTABLE . " WHERE      
        address='" . $_POST['address'] . "' ");
        $balance = 0;
        while($row = mysqli_fetch_assoc($result)) {
           $balance += $row['balance'];
        echo "<font style='font-weight:bold;'>Your current balance is: </font><br/>";
        printf("%0.8f", ($balance / 100000000));