我正在设计这个页面，用户将看到当天的变更单。我只需要一个人一次编辑一个变更单。而其他用户仍可以编辑其他变更单。我粘贴的代码是最后一页，用户在点击特定的变更单后被重定向。请帮我举个例子，因为我对php和mysql非常陌生。提前谢谢`

<?php
$change = $_GET['value'];
mysqli_query('BEGIN');
$sql="SELECT  * FROM cat_firewall USE INDEX(id) WHERE chg_id='$change' FOR UPDATE";
$result=mysqli_query($con,$sql);

// Count table rows 
$count=mysqli_num_rows($result);
?>
---MORE CODE----
while ($row = mysqli_fetch_array($result)){ ?>
        <tr>
---MORE CODE----

<?php

$source_FW = $_POST['source_FW'];
$source_ACL =  $_POST['source_ACL'];
$destination_FW = $_POST['destination_FW'];
$destination_ACL =  $_POST['destination_ACL'];

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

foreach($source_FW as $key=>$value){
$sql1="UPDATE cat_firewall SET source_FW='$value' WHERE entry_id='$key' AND chg_id='$change' ";
$result=mysqli_query($con,$sql1);
}
foreach($source_ACL as $key1=>$value1){
$sql2="UPDATE cat_firewall SET source_ACL='$value1' WHERE entry_id='$key1' AND chg_id='$change'  ";
mysqli_query($con,$sql2);
}
foreach($destination_FW as $key2=>$value2){
$sql3="UPDATE cat_firewall SET destination_FW='$value2' WHERE entry_id='$key2' AND chg_id='$change' ";
mysqli_query($con,$sql3);
}
foreach($destination_ACL as $key3=>$value3){
$sql4="UPDATE cat_firewall SET destination_ACL='$value3' WHERE entry_id='$key3' AND chg_id='$change'  ";
mysqli_query($con,$sql4);
}

echo "update complete";
}

sleep(120);
mysqli_query($con,'COMMIT');
?>'

`