Why won't this Insert INTO Work ? Php
<p>// This is the file that is giving the error, not the form below</p>

<pre><code>       &lt;?php
        // Insert Comments into Database that user provides

&lt;?php
// Insert Comments into Database that user provides
$comm = mysql_real_escape_string($_POST['addComment']);

// following line has changed:
$pID4 = filter_var( $_POST['pID'], FILTER_SANITIZE_STRING );

$cID = mysql_real_escape_string($_POST['courseInfoDD']);
$username = "###";
$password = "###";
$pdo4 = new PDO('mysql:host=localhost;dbname=###', $username, $password);
$pdo4-&gt;setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
$sth4 = $pdo4-&gt;prepare('INSERT INTO Comment (info, pID, cID) VALUES(?,?,?);'); 
$sth4-&gt;execute(array($comm, $pID4, $cID ));

?&gt;
</code></pre>

<p><strong>Form</strong></p>

<pre><code>&lt;input type='text' id='addComment' name='addComment' tabindex='3' value='Enter comment' /&gt;
&lt;input type='hidden' name='pID' value='&lt;?php echo $pID ?&gt;'&gt;
&lt;/form&gt;
</code></pre>

<p><strong>ERROR Received:</strong></p>

<pre><code>*No error is received upon load, but once I type something in and press enter it gives me a blank page saying 'no pID specified' ?? Please help!*
</code></pre>
