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What would be the right setting for a column that should always have a value?


NULL


Primary key


NOT NULL


INTEGER

What is the main benefit of denormalizing a normalized table?


Less data redundancy


Less space needed


More security


Improved speed of data retrieval

When building the Physical Data Model, one of the decisions that needs to be made is...


normalize all relations


insert an instance


define attributes' data type


name the entity

A _______________________ dependency is a functional dependency on non-primary key attributes.


Transitive


Adjacent


Partial


Functional

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