Why is only one table row updated? - php

Question

I'm trying to update the rank column in the users table in MySQL using PHP, but when I try to change the values and press the update button, only the last one of the table rows is actually being updated. Here is an image of what the PHP table looks like on the webpage:
Here is the code:
<?php
include '../db/connect.php';
$con = $MySQLi_CON;
if (!$con){
die("Can not connect: " . mysql_error());
}
if(isset($_POST['update'])){
$UpdateQuery = "UPDATE users SET rank='$_POST[rank]' WHERE user_id='$_POST[hidden]'";
$con->query($UpdateQuery);
}
$result = $MySQLi_CON->query("SELECT * FROM users")
or die(mysql_error());
echo "<table border=1>
<tr>
<th>ID</th>
<th>Username</th>
<th>Email</th>
<th>Rank</th>
</tr>";
echo "<form action='test3.php' method='post'";
while($record = $result->fetch_array()){
echo '<tr>';
echo '<td>' . $record['user_id'] . '</td>';
echo '<td>' . $record['username'] . '</td>';
echo '<td>' . $record['email'] . '</td>';
echo '<td>' . '<input type="number" name="rank' . [$record['user_id']] . '" />';
echo '<td>' . '<input type="hidden" name="hidden" value="' . $record['user_id'] . '"</td>';
echo '<td>' . '<input type="submit" name="update" value="update"' . '</td></tr>';
}
echo "</table>";
for($_POST['rank'] as $user_id=>$rank){
$UpdateQuery = "UPDATE users SET rank='$rank' WHERE user_id='$user_id'";
$con->query($UpdateQuery);
}
$con->close();

Answer 1

The problem is all rank of each row is using the same name rank and also the hidden, the browser will override all rank and hidden value with the latest element.
change <input type="number" name="rank" /> to <input type="number" name="rank[$record['user_id']]" />
receive in php with $_POST['rank'] in array format and loop each rank.
for($_POST['rank'] as $user_id=>$rank){
$UpdateQuery = "UPDATE users SET rank='$rank' WHERE user_id='$user_id'";
$con->query($UpdateQuery);
}