You should also use:
base64_encode() on the data before putting it in the database:
PHP: base64_encode - Manual

And when you want to take it out use:
base64_decode() on the data.
PHP: base64_decode - Manual

Before you display it or download it or whatever.

Good luck.

__________________
Of course the whole point of a doomsday machine, would have been lost if you keep it a secret.