PHP 准备语句不更新 SQL 数据库

Question

这是我第一次深入研究使用准备好的语句来更新 MySQL。不确定我哪里出错了，但是当我点击提交按钮时，页面刷新但没有任何更新实际生效。

<?php session_start();

include_once("../includes/connection.php");
include_once("../includes/product.php");

$product = new Product;
$products = $product->fetch_all();

if (isset($_SESSION['logged_in'])) {

    if (isset($_GET['id'])) {
    $id = $_GET['id'];
    $sql_select = "SELECT * FROM products WHERE product_id = '{$id}'";
    $statement = $pdo->query($sql_select);
    $r = $statement->fetch(PDO::FETCH_ASSOC);
    }

    if (isset($_POST['submit'])) {
    if (isset($_POST['product_name'])) { $name = $_POST['product_name']; }
    if (isset($_POST['product_avail'])) { $avail = $_POST['product_avail']; }
    if (isset($_POST['product_price'])) { $price = $_POST['product_price']; }
    if (isset($_POST['product_desc'])) { $desc = $_POST['product_desc']; }
    if (isset($_POST['image'])) { $img = $_POST['image']; }

    $sql_update = 'UPDATE products SET (product_name, product_avail, product_price, product_desc, image) 
    VALUES (:name, :avail, :price, :desc, :img) WHERE product_id = :id';

    $updstmt = $pdo->prepare($sql_update);
    $updstmt->execute(array(
        ':id' => $id,
        ':name' => $name,
        ':avail' => $avail,
        ':price' => $price,
        ':desc' => $desc,
        ':img' => $img));
    }
?>
    <?php include_once("../includes/header.php"); ?>
        <h4>Edit product</h4>
            <!-- call error if any required fields are empty -->
            <?php if (isset($error)) { ?>
                <small style="color:#aa0000;">* <?php echo $error; ?>
            <?php } ?>
            <form action="edit_test.php?id=<?php echo $_GET['id']; ?>" method="post">
                <small>Product Name</small><br />
                    <input type="text" name="product_name" value="<?php echo $r['product_name']; ?>" <?php if (isset($error) && empty($_POST['product_name'])) { ?> class="error" <?php } ?>/>
                <br /><br />
                <small>Available?</small>
                    <input type="text" name="product_avail" value="<?php echo $r['product_avail']; ?>" <?php if (isset($error) && empty($_POST['product_avail'])) { ?> class="error" <?php } ?>/>
                <small>Price</small>
                &#36;<input type="number" min="0.01" step="0.01" name="product_price" value="<?php echo $r['product_price']; ?>" <?php if (isset($error) && empty($_POST['product_price'])) { ?> class="error" <?php } ?>/>
                <br /><br />
                <small>Product Description</small>
                    <textarea rows="20" cols="30" name="product_desc" <?php if (isset($error) && empty($_POST['product_desc'])) { ?> class="error" <?php } ?>><?php echo $r['product_desc']; ?>    </textarea><br /><br />
            <br /><br />
                <small>Product Image</small>
                <input type="text" name="image" value="<?php echo $r['image']; ?>" <?php if (isset($error) && empty($_POST['i'])) { ?> class="error" <?php } ?>/>

                <input type="submit" value="POST" class="submit save">
            </form>

            <br /><br />
            <small><a href="index.php">&larr; Back</a></small>
        </div>
    <?php include("../includes/footer.php"); ?>
<?php   
}
?>

我哪里错了？

Answer 1

您的UPDATE 语句是错误的。它不应该使用 VALUES。

$sql_update = 'UPDATE products SET product_name = :name, product_avail = :avail, product_price = :price, product_desc = :desc, image = :img WHERE product_id = :id';

在您的页面和 SQL 语句中添加错误检查会发现您的查询是错误的。 总是打开错误检查的代码和删除错误的代码。