Foreach update sql loop don't create loops - php

Question

I have some strange problems with this codes:
The while loopp that contains a form inside
<?php
$sql = "SELECT * FROM sessions WHERE SES = '$SES' ORDER BY ID DESC";
$preorders = mysql_query($sql);
while ($pre = mysql_fetch_array($preorders)) { ?>
<tr>
<td class="center">
<form id="update" action="update" method="post">
<input type="number" name="QTY[]" value="<?=$pre[QTY]?>" min="1" max="100">
<input type="hidden" name="ID[]" value="<?=$pre[ID]?>">
</form></td>
</tr>
<?php } ?>
The submit button
<button type="submit" form="update">Update</button>
Process page
foreach ($_POST['ID'] as $key => $ID) {
$QTY = $_POST['QTY'][$key];
mysql_query("UPDATE sessions SET QTY= '$QTY' WHERE ID = '$ID' ");
}
THE ISSUE
That foreach update only the first item. Mostly, I need to update more than one item. Where is the problem?
Thank you so much!

Answer 1

There are multiple things going wrong with your code. First you use [] in this input's name:
<input type="number" name="QTY[]" value="<?=$pre[QTY]?>" min="1" max="100">
and this input as well:
<input type="hidden" name="ID[]" value="<?=$pre[ID]?>">
You probably want to place them inside <?php ... ?> tags.
Second. You only have one update button but multiple forms. Each form needs its own update button which needs to be included inside each <form> element.
Third. You're using the deprecated mysql functions. Change to mysqli or PDO.
Fourth. You should use Prepared Statements for your update query or else your code is susceptible to SQL Injection.