My client have created a script in php+mysql that saves images directly in the database and every images has url like this: www.example.com/image.php?id=421
In your
If you read @Gazler's link from comment, it really boils down to few questions:
if you answered with answers in brackets, then it might be good for your website to put images out of database, otherwise, you can leave it as it is and save yourself some time and/or nerves