read PDF file, is this correct?

[klemme]

Hi,

After uploading a pdf from a form, i am trying to read the file.

It is saved in DB, and i try to get the chosen PDF via a link that holds a unique value from the DB, so the chosen PDF can be identified, and displayed.

BUT, I only get the eror message from the bottom of the script, so something goes wrong, as I cant read the file, or something in my code is wrong, and doesnt get processed at all?

Does someone know how to do this? To read a PDF file, stored in the DB - and display to the user?

Please, help is needed.
This is the code where I try to display the PDF (Not working)

<?php require_once("includes/config.php"); ?>
<?php require(MYSQL); ?>
<?php
$valid = false;
if(isset($_GET['id'])&&(strlen($_GET['id'])==40)&&(substr($_GET['id'],0,1)!='.')){
$file = PDFS_DIR .$_GET['id'];
//echo $file;
		
if(file_exists($file) && (is_file($file))){
$query = 'SELECT title, description, file_name, FROM pdfs WHERE tmp_name='.mysqli_real_escape_string($connection, $_GET['id']).'';
$result = mysqli_query($connection, $query);

if(mysqli_num_rows($result) == 1){//OK!
	 $row = mysqli_fetch_array($result, MYSQLI_ASSOC);
	 $description = $row[3];
	 $valid = true; 

	 $fs = filesize($file);
	 
	 header("Content-Length: $fs\n");	 
	 header('Content-type: application/pdf');
	 header('Content-Disposition: inline;filename="'.$row['file_name'].'"');	
	 
	 readfile($file);	
	 //die(); 	 
			}
		}
	}
?>

<?php
// Further down the page:
if($valid != true){ // error msg.
echo'<h4>Der er sket en fejl og PDF-filen kunne ikke vises. 
Vi beklager ulejligheden, og vil løse problemet hurtigst muligt, da vores Administrator er blevet automatisk informeret!</h4>';	
}else {
echo "<div>$description</div>";	
}
?>

I have defined the PDF_DIR like this: (Is that correct?)

define('PDFS_DIR', $_SERVER['DOCUMENT_ROOT']);

Is this part correct?