Instruction
5. Consider the following 3NF relations about a sorority or fraternity:
MEMBER(Member_ID,Name ,Address,Dues_Owed)
OFFICE(Office_Name,Officer_ID,Term_Start_Date, Budget)
EXPENSE(Ledger_Number ,Office_Name,Expense_Date, Amt_Owed)
PAYMENT (Check_Number,Expense_Ledger_Number, Amt_Paid)
RECEIPT(Member_ID,Receipt_Date,Dues_Received) COMMITIEE(Committee_ID,Officer_ in_Charge) WORKERS(Committee_ID,Member_ID)
a. Foreign keys are not indicated in these relations. Decide which attributes are foreign keys and justify your decisions.
b. Draw an E-R diagram for these relations, using your answer to Problem and Exercise 5a.
c. Explain the assumptions you made about cardinalities
in your answer to Problem and Exercise 5b. Explain why it is said that the E-R data model is more expressive or more semantically rich than the relational data model.