Your question is kind of complicated thou as I think. I divided it in two part:
1. Admin Access
2. Unauthorised Access
1. Admin Access: If I took that admin have a hosting website Coupon Codes for Hostgator which database which is access by two master password like
i). abcd to open the database and show all the details
ii). wxyz to delete all the database
This both can happen when the admin are logged in.
I take the example of facebook where you can download all your previous data and delete all the data at the same platform.
2. Unauthorised Access: In this situation if a unauthorised user are trying to breach a password protected security then we can block his ip for lifetime.
But as loveworksdotcom said is very harmful for your own database cus there are more than 80 attempts happen regular on a avg. website.
