Learn MVC Architecture.
Then implementing the Jsp Model 2 Architecture, which is similar to MVC
will be a nice idea.
As you are looking for Database to be there, The Model Part will communicate with the DB.
Presntation would be taken care by JSP(View).
And all the contols would be done by Controller(Your's
Servlet).
Now what do you exactly want to implement, is your's choice and interest.
Hope it would give you some idea.