Database Past Paper Help

I need help with a database past paper, our professors did not provide us with solutions, so I don't know whether my answers are correct or not.

I would appreciate if an expert could provide me with some example answers.

1. (a) What is normalisation in the context of relational database design? Explain whether it is always desirable to normalise relations into Third Normal Form. 13] (b) The following is an example of an order placed by a customer with a self-explanatory order form: 102369 17/03/2010 103423 No Order Date Customer ID Customer Name John Smith Delivery Address 123 Main Road, Cardiff, CF12 3AB Item No 1023-01 2137-12 7387-15 Total Amount51.20 Description Item Price() Quantity Cost() A4 Paper DVD-R Disk Batteries 1.20 0.70 2.30 6 30 10 7.20 21.00 23.00 Using this form i. derive a single First Normal Form relation (only the schema is required and the primary key should be underlined); 2 ii. identify the functional dependencies that you woulkd expect to hold among the attributes in your First Normal Form relation and express them in a functional dependency diagram (state say assumptions you make);: your First Normal Form relation into a set of Third Normal Form tables (primary keys should be ii. nomalise underlined) (c) Assume that we have a relation with three attributes: R(A, B,C), and AB and B C (functional dependen- cies) hold in R. Use Armstrong rules to show that A BC also holds. [3