Question

40. suppose I am modeling a bank. For a CUSTOMER entity, explain why a customer's social security number is a better identifier than (LastName, FirstName).

39. Suppose I want to model an online retailer. Customers may choose to have the order delivered to one of multiple addresses which are saved in the database.

What type of attribute does "Address" represent and how should I handle it in my model. You do not need to include any discussion of cardinalities as part of your answer.

Answer 1

Hi,

40. It is better to use a customer's social security number than using a (Lastname,firstname) to identify a customer.A Social Security Number is a unique number which is assigned to every people.So on using this number it will never difficult to identify the customer.Here it is modelling a bank,so there is so much transactions are all going to happen.So customer identification is a must.There is more chance for a person having same name,even the first name and last name.So it is difficult to identify person uniquely.For verification of a social security number it consist of identification number,social security number,firstname,lastname,address,date of birth.So on using Social Security Number all information about the customer is available.So it is better to use Social Security Number.

39. For online retailing it is must to know the address of a customer.An address is a multivalued type attribute.Because it consist of different field.That is an address consist of House name,locality,city,state,PIN number.So by using the fiels it is better to identify the correct customer.In this model Address part should include the above fields.

Thank you...