Can't delete a row from a Database using a img PHP - php

Question

i was doing a backoffice for my website, and to show the data i brought a table from database to show all the upgrades requested from users, and i was thinking about putting 2 images , one for update and another for deleting that same row..
# Table from Database #
?>
<div id="DBForm">
<p id="title" align="center"> Upgrades</p>
<br/>
<?php
$resultado=mysql_query("SELECT * FROM upgrades");
if (mysql_affected_rows()>=1)
{
echo "<table class='DBTable'>";
echo "<tr>
<th>Nome</th>
<th>Upgrade</th>
<th>Morada</th>
<th>Contacto</th>
<th>NIF</th>
<th>Factura</th>
<th>Data</th>
<th>N Serie</th>
<th>Cupao</th>
<th>Alterar</th>
<th>Eliminar</th>
</tr>";
while ($linha=mysql_fetch_array($resultado))
{
echo "<tr align='center'>
<td>".$linha["nome"]."</td>
<td>".$linha["upgrade"]."</td>
<td>".$linha["morada"]."</td>
<td>".$linha["contacto"]."</td>
<td>".$linha["nif"]."</td>
<td>".$linha["factura"]."</td>
<td>".$linha["data_factura"]."</td>
<td>".$linha["n_serie"]."</td>
<td>".$linha["cupao"]."</td>
<td><img src=images/alterar.png></img> </td>
<td><img src=images/eliminar.png></img> </td>
</tr>";
}
echo "</table>";
}
?>
</div>
It was all right, but when i press the img to delete, the browser says that i sucessfully deleted the row but when i go back to the page the row is still there, what it could be ?
#Code from img to delete the row#
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "loja";
$tbl_name = "upgrades";
// Create connection
mysql_connect($servername, $username, $password)or die ("Não houve conexão");
mysql_select_db("$dbname");
$id=$_REQUEST['id'];
$sql="DELETE FROM $tbl_name WHERE id='$id'";
$result=mysql_query($sql);
if ($result)
{
echo "Registo apagado com sucesso!";
echo "<br>";
echo "<a href='upgrades.php'> Voltar a upgrades </a>";
}
else
{
echo "ERRO!";
mysql_close();
}
?>

Answer 1

Nothing is supplying this value:
$id=$_REQUEST['id'];
The page is being requested with just a link:
"<img src=images/eliminar.png>"
In order to supply the identifier you'll need to add it to the link. Maybe something like this:
"<img src=\"images/eliminar.png\">"
(or whatever the identifier is on $linha)
Additionally, please be aware that your code is wide open to SQL injection attacks. You'll want to look into using prepared statements instead of putting user input directly into SQL code.
Sidenote: You can safely remove the </img> tag; it's not a valid tag.