如何使用mysql查询在php中使用嵌套的foreach循环

大家好，我正在尝试使用2个嵌套的foreach循环在表中插入/更新数据。。。 我有桌子-

1。温度

供应商标识|部件|数量

2。股票

库存|部件|数量

首先，我选择了一个临时表，在3次检查的基础上将数据传输到库存表-

若库存表中的现有值和临时表中的库存ID和组件相同，则更新库存表中的现有值

如果库存表中没有与该库存ID对应的组件，则在库存表中插入新条目

在库存表中插入新条目，前提是该条目具有组件，但与库存表中的任何库存ID均不对应

---

注意-临时表中的供应商ID与库存表中的库存ID相同。

单个foreach更有用，您不需要嵌套的foreach查询

$sql = "SELECT * FROM sample.temp";
$query = $dbo->prepare($sql);
$query->execute();

$result = $dbo->fetchAll(PDO::FETCH_ASSOC);
if(!empty($result)) {
    foreach($result as $item) {
    $Qty = $item['Qty'];
    $component = $item['component'];
    $vendor_ID = $item['vendor_ID'];

    $sql = "SELECT * FROM sample.stock WHERE stock_ID = :vendor_ID";
    $query = $dbo->prepare($sql);
    $query->bindValue(':temp_stock', $vendor_ID);
    $query->execute();
    $result = $query->fetch(PDO::FETCH_ASSOC);

        if (!empty($result)) {
            $sql = "UPDATE sample.stock SET Qty = (Qty + :Qty) WHERE stock_ID = :vendor_ID AND component= :component";
            $query = $dbo->prepare($sql);
            $query->bindValue(':vendor_ID', $vendor_ID);
            $query->bindValue(':component', $component);
            $query->bindValue(':Qty', $Qty);
            $query->execute();

            if ($query->rowCount > 0) {
            echo "Success: Updated $vendor_ID quantity";
            } else {
            echo "Error: Failed to modify $vendor_ID quantity";
            }

        } else {
            $sql = "INSERT INTO sample.stock (stock_ID, component, Qty) VALUES ($vendor_ID, '$component', $Qty)";
            $query = $dbo->prepare($sql);
            $query->bindValue(':vendor_ID', $vendor_ID);
            $query->bindValue(':component', $component);
            $query->bindValue(':Qty', $Qty);
            $query->execute();

            if ($query) {
            echo "Success: Added $vendor_ID";
            } else {
            echo "Error: Failed to add $vendor_ID";
            }
        }
    }
} else {
echo "No results in temp table";
}`

---

那么，实际的问题是什么？@Epodax插入查询无限地插入值。。。我不知道如何使用nested foreach对两个表中的每个组件进行条件检查……有任何更新吗？@iamgory我自己解决了这个问题，但您的代码也是正确的！谢谢

$sql = "SELECT * FROM sample.temp";
$query = $dbo->prepare($sql);
$query->execute();

$result = $dbo->fetchAll(PDO::FETCH_ASSOC);
if(!empty($result)) {
    foreach($result as $item) {
    $Qty = $item['Qty'];
    $component = $item['component'];
    $vendor_ID = $item['vendor_ID'];

    $sql = "SELECT * FROM sample.stock WHERE stock_ID = :vendor_ID";
    $query = $dbo->prepare($sql);
    $query->bindValue(':temp_stock', $vendor_ID);
    $query->execute();
    $result = $query->fetch(PDO::FETCH_ASSOC);

        if (!empty($result)) {
            $sql = "UPDATE sample.stock SET Qty = (Qty + :Qty) WHERE stock_ID = :vendor_ID AND component= :component";
            $query = $dbo->prepare($sql);
            $query->bindValue(':vendor_ID', $vendor_ID);
            $query->bindValue(':component', $component);
            $query->bindValue(':Qty', $Qty);
            $query->execute();

            if ($query->rowCount > 0) {
            echo "Success: Updated $vendor_ID quantity";
            } else {
            echo "Error: Failed to modify $vendor_ID quantity";
            }

        } else {
            $sql = "INSERT INTO sample.stock (stock_ID, component, Qty) VALUES ($vendor_ID, '$component', $Qty)";
            $query = $dbo->prepare($sql);
            $query->bindValue(':vendor_ID', $vendor_ID);
            $query->bindValue(':component', $component);
            $query->bindValue(':Qty', $Qty);
            $query->execute();

            if ($query) {
            echo "Success: Added $vendor_ID";
            } else {
            echo "Error: Failed to add $vendor_ID";
            }
        }
    }
} else {
echo "No results in temp table";
}`