PHP to store images in MySQL or not?

Question

I have built a small web application in PHP where users must first log in. Once they have logged in, I intend on showing a small thumbnail as part of their \"profile\".

Answer 1

1. What's the blob datatype for anyway, if not for storing files?
2. If your application involves authorisation prior to accessing the files, the changes are that you're a) storing the files outside of DOCUMENT_ROOT (so they can't be accessed directly; and possibly b) sending the entire contents of the files through the application (of course, maybe you're doing some sort of temporarilly-move-to-hashed-but-publicly-accessible-filename thing). So the memory overhead is there anyway, and you might as well be retrieving the data from the database.
3. If you must store files in a filesystem, do as Andreas suggested above, and name them using something you already know (i.e. the primary key of the relevant table).