Homework 7 (due 11/8)


Homework is due by classtime on Thursday. Submit either a hardcopy (in class, or drop it off at the 4th floor front desk), or email it to me.

We continued ER-modeling and EER modeling (see chapter 3 of the book).

This is a light homework so you have time to work on your ER model for the final project.


1.  [The bank's miniworld] 

We want to design a database for a small bank

"For customers we store name, address, and SSN, and we give them a unique ID. We offer three types of accounts to our customers: checking, saving, and money market. All of these accounts have a unique account_nr, current balance, and the day they were opened. The checking account has a service charge associated with it, and both the saving and money market accounts an interest_rate. The money market account, furthermore, has a minimum balance. Customers can deposit money into any of these accounts freely; we need to store the amount and the time for such a transaction. We also keep track of customer's check transactions (amount, time), but we only allow checks for our checking accounts. The saving account comes with an ATM card, again we keep track of transactions (amount, time, type [deposit, withdrawal]).

Based on this description, design an EER diagram for the bank. Think carefully about what objects should become entities and which relations you want. Add all the attributes you need, and finally include key and minimum/maximum cardinality constraints. 


Marcus Schaefer
Last updated: November 1st, 2007.