How to destroy the current image in image upload - php

Question

I want to do is when a user decided to change his profile picture the link in the database will be update and move the image to upload folder and destroy the current link and image on the upload folder on that specific user.
My problem in my code is when a user change his profile picture it will add another picture on the upload folder. I want to do is to delete the current image first on that specific user before the new image he selected is move on the upload folder.
php code
<?php
include_once('../dbc/database.php');
$db = new Connection();
$db = $db->dbConnect();
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$email = isset($_POST['email']) ? $_POST['email'] : "";
$image = addslashes(file_get_contents($_FILES['imageInput']['tmp_name']));
$image_name = addslashes($_FILES['imageInput']['name']);
$image_size = getimagesize($_FILES['imageInput']['tmp_name']);
move_uploaded_file($_FILES["imageInput"]["tmp_name"], "../upload/" . $_FILES["imageInput"]["name"]);
$location = "elogFiles/upload/" . $_FILES["imageInput"]["name"];
$qOldpic = "SELECT user_image FROM tbl_user WHERE user_email = : email";
$queryOldpic = $db->prepare($qOldpic);
$queryOldpic->bindParam(':email', $email);
$queryOldpic->execute();
$num_rows = $queryOldpic->rowCount();
if ($num_rows == 1) {
unlink($queryOldpic);
$q = "UPDATE tbl_user SET user_image = '$location' WHERE user_email= :email ";
$query = $db->prepare($q);
$query->bindParam(':email', $email);
$results = $query->execute();
echo "1";
}
?>

Answer 1

http://php.net/manual/en/function.unlink.php
above url will help you understand proper approach to delete the previous image file.
If you want to make the error message invisible when that file is not exist on given location, use '#' so you could simply ignore the error display as the following:
<?php
unlink($filename);
?>

Answer 2

Before you do your update, run a select and get the user_image by email, store it into a variable, like $oldPicture.
After that, you should remove the picture like this:
if ((!!$oldPicture) && (file_exists($oldPicture))) {
unlink($oldPicture);
}
You only delete an image if you have a value for its path and the file exists. Make sure the path of $oldPicture is correct. Finally, after the if above you can run your update command. I will not delve into security problems, as it is out of scope in this question, but make sure you prevent SQL injection.