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When mapping a Conceptual Model to a Relational Model, a simple identifier maps to ...


a composite attribute.


a column.


a simple attribute.


a simple key.

When transforming a Conceptual Model Entity to a Relational Model Relation, each simple attribute maps to ...

a composite attribute.


a column.


a relation.


a relationship.

Select the correct statement about Relations in the Relational Data Model.


Having multiple attributes with the same provides redundancy.


There can be composite attributes.


Multiple relations with the same name provide redundancy.


There cannot be multivalued attributes.

The process of defining a more general entity type from a set of more specialized entity types is called:


Specialization


Generalization


Normalization


Extrapolation

A supertype entity Vehicle in the Division of Motor Vehicles' database has the following attributes: VIN, Make, Model, Color, VehicleType.
VIN is the identifier and joins the Vehicle entity to these entities: Car, Truck, Bus and Bike
Because Car, Truck, Bus and Bike inherent the attributes mentioned above from Vehicle, they are called ___________________.

Supertype
Subtype
Strong
Associative

At company X, an Employee may have none or many Dependents. A Dependent may only be in a single Employee's insurance. What is the cardinality of the relationship between Employee and Dependent?

Unary
One-to-Many
One-to-One
Many-to-Many

In an entity, an identifier is an attribute that uniquely identifies an instance of the entity. If ID is an integer attribute and is the identifier of entity X, how many times can ID 10 appear?

Once
Up to 10 times only
Never because it is the identifier
As many times as needed because it is the identifier

A Unary relationship involves how many entities?

1
2
0 or more
3

What is the data model that contains the business requirements for the database?

The Logical
The Enterprise
The Conceptual
The Physical

Which data model is used to build the database?

The Enterprise
The Conceptual
The Physical
The Logical