使用html表单更新mysql数据库内容的问题

Question

我有一个页面，我正在制作一个非常简单的CMS，页面显示3个产品，它从数据库中获取标题，描述，价格，产品包含和产品不包括。这工作，不起作用的是我创建的一个表单，可以轻松更改我的数据库中的内容。现在，当我填写表单时，不是将表单中的所有数据添加到数据库，而是添加除最后一个输入字段之外的表单中的所有数据。如果我只尝试使用单个字段更新数据库中的单个项目，那么只有该项目会更新，但所有其他项目都会被删除。

这是我的代码。

 <h2>Deal 1</h2>
    <form method="POST" action="#">

        <table>
            <tr>
                <td><label>Title: </label><br><input type="text" name="title1" placeholder="<?php echo htmlspecialchars($deal1title); ?>"></td>
            </tr>

            <tr>
                <td>
                    <label>Description: </label><br><textarea style="height: 200px;" name="desc1" placeholder="<?php echo htmlspecialchars($deal1desc); ?>"></textarea>
                </td>
            </tr>

            <tr>
                <td><label>Price: </label><br><input type="text" name="price1" placeholder="<?php echo htmlspecialchars($deal1price); ?>"></td>
            </tr>

            <tr>
                <td><label>Include: </label><br><input type="text" name="include1" placeholder="<?php echo htmlspecialchars($deal1inc); ?>"></td>
            </tr>

            <tr>
                <td><label>Not Include: </label><br><input type="text" name="notinc1" placeholder="<?php echo htmlspecialchars($deal1noinc); ?>"></td>
            </tr>

            <tr>
                <td><input type="submit" name="submit1" value="Save"></td>
            </tr>

        </table>

    </form>

这是连接

<?php

    $connect =mysqli_connect('localhost', 'root', 'password', 'specials' );

//Error Check//

    if(mysqli_connect_errno($connect)){
            echo "failed to connect";}


    $fetcher = mysqli_query($connect, "SELECT * FROM specials WHERE id=1");

    $fetcher2 = mysqli_query($connect, "SELECT * FROM specials WHERE id=2");

    $fetcher3 = mysqli_query($connect, "SELECT * FROM specials WHERE id=3");

    $deal1 = mysqli_fetch_array($fetcher);
    $deal2 = mysqli_fetch_array($fetcher2);
    $deal3 = mysqli_fetch_array($fetcher3);


    //Insert Data
    //mysqli_query($connect, "INSERT INTO deal_1 (title) VALUES ('Galapagos')");
    //Deal 1
    $deal1title=$deal1["title"];
    $deal1desc=$deal1["description"];
    $deal1price=$deal1["price"];
    $deal1inc=$deal1["include"];
    $deal1noinc=$deal1["notinclude"];

这是我的数据库更新表单

        <h2>Deal 1</h2>
    <form method="POST" action="#">

        <table>
            <tr>
                <td><label>Title: </label><br><input type="text" name="title1" placeholder="<?php echo htmlspecialchars($deal1title); ?>"></td>
            </tr>

            <tr>
                <td>
                    <label>Description: </label><br><textarea style="height: 200px;" name="desc1" placeholder="<?php echo htmlspecialchars($deal1desc); ?>"></textarea>
                </td>
            </tr>

            <tr>
                <td><label>Price: </label><br><input type="text" name="price1" placeholder="<?php echo htmlspecialchars($deal1price); ?>"></td>
            </tr>

            <tr>
                <td><label>Include: </label><br><input type="text" name="include1" placeholder="<?php echo htmlspecialchars($deal1inc); ?>"></td>
            </tr>

            <tr>
                <td><label>Not Include: </label><br><input type="text" name="notinc1" placeholder="<?php echo htmlspecialchars($deal1noinc); ?>"></td>
            </tr>

            <tr>
                <td><input type="submit" name="submit1" value="Save"></td>
            </tr>

        </table>

    </form>

这是我的db update php代码

 <?php

    //Get Data Deal 1

    if(isset($_POST['submit1'])){

    $getTitle1=$_POST["title1"];
    $getDesc1=$_POST["desc1"];
    $getPrice1=$_POST["price1"];
    $getInc1=$_POST["include1"];
    $getNoInc=$_POST["noinc1"];
        //Set Title
        if(!empty($getTitle1)){
        mysqli_query($connect, "UPDATE specials SET title='$getTitle1' WHERE id='1'");
        }
        //Set Description
        if(!empty($getDesc1)){
            mysqli_query($connect, "UPDATE specials SET description='$getDesc1' WHERE id='1'");    
        }
        //Set Price
        if(!empty($getPrice1)){
        mysqli_query($connect, "UPDATE specials SET price='$getPrice1' WHERE id='1'");
        }
        //Set Include
        if(!empty($getInc1)){
            mysqli_query($connect, "UPDATE specials SET include='$getInc1' WHERE id='1'");
        }
        //Set noinclude
        if(!empty($getNoInc)){
            mysqli_query($connect, "UPDATE specials set notinclude='$getNoInc' WHERE id='1'");
        }


    }