Question

我有一个PHP代码，它总结了通过多个表的列，并在查询完成后返回3个单独的总金额，因为我有3个表。如果我想将这3个总金额合并为一个，我需要以什么方式更改代码才能实现这一目标？

foreach($result as $row) {
  $stmt1 = $DB_CON_C->prepare("SELECT SUM(total_fee) AS total_amount FROM `".$row['files']."`");
  $stmt1->execute();
  $sum1 = $stmt1->fetch(PDO::FETCH_ASSOC);

  echo $sum1['total_amount'];
}

Answer 1

尝试这样的事情：

$totalAmount = 0;

foreach($result as $row) {
    $stmt1 = $DB_CON_C->prepare("SELECT SUM(total_fee) AS total_amount FROM `".$row['files']."`");
    $stmt1->execute();

    $sum1 = $stmt1->fetch(PDO::FETCH_ASSOC);

  totalAmount += $sum1['total_amount'];
}

echo $totalAmount;

只需在循环搜索之外创建一个变量并加起来即可。

Answer 2

尝试这样的事情。在循环外创建一个变量，然后按循环递增它。

$grandTotal = 0;
foreach($result as $row) {
  $stmt1 = $DB_CON_C->prepare("SELECT SUM(total_fee) AS total_amount FROM `".$row['files']."`");
  $stmt1->execute();
  $sum1 = $stmt1->fetch(PDO::FETCH_ASSOC);

  $grandTotal = $grandTotal +  $sum1['total_amount'];
}
echo $grandTotal;

不确定这是否有效，但你明白了。

php sum列在多个表中并返回为一个总计

2 个答案: