php - 在 PHP 中构建多维数组时更新其内的值

Question

我有一个 MySQL 查询:

SELECT id, order_no, reference, description, total_cost FROM bookorders

while 循环中的结果正在构建一个数组:

if (!array_key_exists($order_no, $orders)) {
    $orders[$order_no] = array(array(
        'reference' => $reference,
        'description' => $description, 
        'total_cost' => $total_cost,
        'discount' => 0,
        'total_cost_withdiscount' => $total_cost
    ));
} else {
    $orders[$order_no][] = array(
        'reference' => $reference,
        'description' => $description, 
        'total_cost' => $total_cost,
        'discount' => 0,
        'total_cost_withdiscount' => $total_cost
    );
}

这就是它的样子:

Array
(
    [12345] => Array
        (
            [0] => Array
                (
                    [reference] => abc
                    [description] => Book Product 1
                    [total_cost] => 8.99
                    [discount] => 0
                    [total_cost_withdiscount] => 8.99
                )   
        )  
    [67890] => Array
        (
            [0] => Array
                (
                    [reference] => abc
                    [description] => Book Product 1
                    [total_cost] => 8.99
                    [discount] => 0
                    [total_cost_withdiscount] => 8.99
                )
            [1] => Array
                (
                    [reference] => def
                    [description] => Book Product 2
                    [total_cost] => 24.99
                    [discount] => 0
                    [total_cost_withdiscount] => 24.99
                )
        )
)

在同一个表中还有折扣行，因此对于订单 67890，有 8 折扣供引用 def。

在运行查询结果时(这会将折扣作为单独的行显示)，如何找出该引用是否已存在并更新“discount”和“total_cost_withdiscount”值？

因此，对于上面的示例，我想更改此:

[67890] => Array
        (
            [0] => Array
                (
                    [reference] => abc
                    [description] => Book Product 1
                    [total_cost] => 8.99
                    [discount] => 0
                    [total_cost_withdiscount] => 8.99
                )
            [1] => Array
                (
                    [reference] => def
                    [description] => Book Product 2
                    [total_cost] => 24.99
                    [discount] => 0
                    [total_cost_withdiscount] => 24.99
                )
        )

对此:

[67890] => Array
        (
            [0] => Array
                (
                    [reference] => abc
                    [description] => Book Product 1
                    [total_cost] => 8.99
                    [discount] => 0
                    [total_cost_withdiscount] => 8.99
                )
            [1] => Array
                (
                    [reference] => def
                    [description] => Book Product 2
                    [total_cost] => 24.99
                    [discount] => 8.00
                    [total_cost_withdiscount] => 16.99
                )
        )

当我在 mysql 查询的 while 循环内构建整个数组时，我需要更新这些值。我已经尝试过，但没有成功:

if ($orders[$order_no]["reference"] == $reference)

编辑

折扣是同一表中的另一行，因此折扣金额将显示为 $total_cost。

所以对于上面的内容，它是:

$id, $order_no, $reference, $description, $total_cost
1, 12345, abc, Book Product 1, 8.99
2, 67890, abc, Book Product 1, 8.99
3, 67890, def, Book Product 2, 24.99
4, 67890, def, discount, 8.00

Answer 1

$reference_to_find = 'def';
$order_no_to_find = 12345;
foreach ($orders as $order_no => $infos)
{
    if ($order_no  == $order_no_to_find)
    {
        foreach ($infos as $index => $item)
        {
            if ($item['reference'] == $reference_to_find)
            {
                // change
                // $item['discount'] = ....

                // set
                $orders[$order_no][$index] = $item;
            }
        }
    }
}