无法执行插入查询？

Question

你能帮我解决这个问题吗？我试图将数据插入我的数据库,而不是插入die()输出; 出现

<?php
    if (isset($_GET['submit'])) {
        $item_code = mysqli_real_escape_string($conn, $_GET['item_code']);
        $item_name = mysqli_real_escape_string($conn, $_GET['item_name']);
        $supplier = mysqli_real_escape_string($conn, $_GET['supplier_name']);
        $brand = mysqli_real_escape_string($conn, $_GET['brand_name']);
        $quantity = mysqli_real_escape_string($conn, $_GET['quantity']);
        $unit = mysqli_real_escape_string($conn, $_GET['unit_name']);
        $price = mysqli_real_escape_string($conn, $_GET['price']);
        $item_type = mysqli_real_escape_string($conn, $_GET['type_name']);
        $category = mysqli_real_escape_string($conn, $_GET['cat_name']);

        if ($item_code == '' || $item_name == '' || $supplier == '' || $brand == '' ||
            $quantity == '' ||
            $unit == '' ||
            $price == '' ||
            $item_type == '' ||
            $category == ''
        ) {
            header("Location: item.php?attempt=empty");
        } else {
            $sql = mysqli_query($conn, "INSERT INTO itemlist (item_name,supplier_name,brand_name,quantity,unit_name,price,type_name,cat_name)    values('$item_name','$supplier','$brand','$quantity','$unit','$price','$item_type','$category')")

            or die("Could not execute the insert query.");
            header("Location: item.php?attempt=saved");
        }
    } 
?>

Answer 1

1）添加item_code插入查询。

<?php
    if (isset($_GET['submit'])) {
        $item_code = mysqli_real_escape_string($conn, $_GET['item_code']);
        $item_name = mysqli_real_escape_string($conn, $_GET['item_name']);
        $supplier = mysqli_real_escape_string($conn, $_GET['supplier_name']);
        $brand = mysqli_real_escape_string($conn, $_GET['brand_name']);
        $quantity = mysqli_real_escape_string($conn, $_GET['quantity']);
        $unit = mysqli_real_escape_string($conn, $_GET['unit_name']);
        $price = mysqli_real_escape_string($conn, $_GET['price']);
        $item_type = mysqli_real_escape_string($conn, $_GET['type_name']);
        $category = mysqli_real_escape_string($conn, $_GET['cat_name']);

        if ($item_code == '' || $item_name == '' || $supplier == '' || $brand == '' ||
            $quantity == '' ||
            $unit == '' ||
            $price == '' ||
            $item_type == '' ||
            $category == ''
        ) {
            header("Location: item.php?attempt=empty");
        } else {
            $sql = mysqli_query($conn, "INSERT INTO itemlist (item_code,item_name,supplier_name,brand_name,quantity,unit_name,price,type_name,cat_name)    values('$item_code','$item_name','$supplier','$brand','$quantity','$unit','$price','$item_type','$category')")

            or die("Could not execute the insert query.");
            header("Location: item.php?attempt=saved");
        }
    } 
?>

2）解决这个问题的另一种方法是将你的定义item_code为primary key。

3) 其他方法是定义item_code任何默认值，如 0。