Hi everyone, i need some help with the theory to complete my upload system.

Well i have two files, the first with html code and some php code and the last with all php code to upload the image, it is some like it:

File1.php
PHP Code:
<?php
    require_once 'config.php';
?>

<!DOCTYPE html>
<html>
<head>
<script src="js/code.js"></script>

</head>
    <body>
        <form id="" action="upload_image.php" method="post" enctype="multipart/form-data" target="upload_target">
            <div id="PhotoInsert">
                <input id="file" type="file" name="file"/> 
            </div>
            <div id="">
                <input id="submit" type="submit" name="submit" value="Submit"/>  
            </div>
            <iframe id="upload_target" name="upload_target" src=""></iframe>
        </form>
    </body>
</html>
upload_image.php
PHP Code:
 Well this file have the code to upload image to database, it is working great. 
Well the upload image is working, now i need to, when i upload the image to the database the upload_image.php return the image url to the iframe and then it will pass to a image src. it will work with ajax, i click on the button (submit) inside of the form and then it will run the upload_image.php code it will send the image to server and will return the image URL and now i dont know how i should do from here to the front, i want to return this URL get it and show that URL inside of a img tag that will be created using jquery. Any tips?

Thanks community