1. Match the type of Unique Identifier to the entity.
a. Simple UID
b. Composite UID
c. Composite UID comprising an attribute and a relationship
d. Primary Key & Secondary Key
D
C
B
A
2. Describe how you would identify the entities listed below, making up any attributes and relationships you consider
appropriate. For example, for the Student entity you may say that the UID is comprised of the first name, last name, and
address. Or you might suggest that the Student entity contains an artificial UID called student number.
a. A city –
comprised of Composite UID: location, name of city
b. A contact person for a customer –
comprised of Artificial UID Primary Key: customer number
Secondary Key: address
Composite Secondary Key: first name, last name
c. A train –
UID comprised of: Artificial Primary Key: train number
Secondary Key: location, size
d. A road –
UID comprised of: Artificial Primary Key: road number
Composite Secondary Key: state, city
3. When checking a database model for first normal form, what are you doing exactly?
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- Fall '13
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