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Which one below is the accepted level of Normalization?


5NF


4NF


3NF


2NF

A EMPLOYEE relation has the following attributes: EmployeeID, EmployeeName, BirthDate, CourseID, CourseTitle, DateCompleted

There is one row for each Course completed by an employee. There is currently one employee that completed the Security course.

What type of anomaly would surface if that employee row were removed?



Addition Anomaly


Deletion Anomaly


Update Anomaly


Insertion Anomaly

Select all possible anomalies not present in a relation in 3rd Normal Form. (The correct answer may require multiple selections)


Insertion Anomaly


Addition Anomaly


Modification Anomaly


Deletion Anomaly

When transforming an ERD of a Conceptual Model to a Relational Model, a many-to-many unary relationship is replaced by ...


a primary key.


two relations.


one relation and one relationship.


a foreign key.

Referential integrity refers to maintaining consistency of values about the same attribute across relations. For instance, in a database that has a State relation with a state_code column for the two-character state codes, there cannot be another relation referencing that State relation with state_code values other than the ones in the State relation.

What component of the Relational Model would enforce such referential integrity?


a Foreign Key


a Primary Key


a Relation


Index

For a single column to be a primary key, what specific condition is required by the Relational Model?


Must include NULL


Must have unique values


Must have unique values not including NULL


Must be multivalued

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