警告

Question

你好，有人可以帮助我，我无法更新我的mysql数据库中的数据

<?php
    require "connection.php";

    $item_name = "cheese";
    $item_code = 123;
    $item_description = "cheese is good";
    $item_unit_price  = 235;

    $mysql_query = "UPDATE Stock SET item_code = '$item_code',item_description = '$item_description',item_unit_price = '$item_unit_price' where item_name='$item_name')";

    //execute the query
    $result = mysqli_query($conn,$mysql_query);


    if($conn->query($mysql_query) ===TRUE){


    echo "Stock Item Updated Successfully";


    }else{

        echo 'Error'.$mysql_query."<br>".$conn->error;
    }

    $conn->close();

    ?>

Answer 1

您的问题可能就在这一行：

$mysql_query = "UPDATE Stock SET item_code = '$item_code',item_description = 
'$item_description',item_unit_price = '$item_unit_price' where item_name='$item_name')";

特别是')";

当你从未打开支架时，你正在关闭支架。

Answer 2

除了非常明显的SQL注入风险之外，还有一些问题与您的代码相关。

从查询中删除)括号

$mysql_query = "UPDATE Stock SET item_code = '$item_code',item_description =
'$item_description',item_unit_price = '$item_unit_price' where
item_name='$item_name')";
                    //^ remove the bracket
//execute the query
$result = mysqli_query($conn,$mysql_query);

//Executing the query again?
if($conn->query($mysql_query) ===TRUE){

您正在执行两次查询。删除其中一行：

$result = mysqli_query($conn,$mysql_query);

或者：

if($conn->query($mysql_query) ===TRUE)

警告

如果这些变量是来自用户的输入，请使用prepared statement来反击SQL注入。像：

$mysql_query = "UPDATE Stock SET item_code = ?, item_description =?, item_unit_price = ? where item_name=?";
$stmt = $mysqli->prepare($mysql_query);
$stmt->bind_param("isds", $item_code, $item_description, $item_unit_price, $item_name);
$stmt->execute();

Answer 3

首先尝试删除结束括号，通过注释//$result = mysqli_query($conn,$mysql_query);来删除其中一个查询执行

Answer 4

试试这个.. !!

<?php 
    $item_name = "cheese";
    $item_code = 123;
    $item_description = "cheese is good";
    $item_unit_price  = 235;


    $mysql_query = "UPDATE Stock SET item_code = '$item_code',item_description = '$item_description',item_unit_price = '$item_unit_price' where item_name='$item_name'";
    //execute the query
    $result = mysqli_query($conn , $mysql_query);
    if($result){
    echo "Stock Item Updated Successfully";
    }else{   
        die('Invalid query: ' . mysqli_error($conn));
    }

    $conn->close();

?>

无法使用mysqli更新MySQL数据库中的数据

4 个答案:

警告