Database Design & Implementation Final Exam

Question 1

A data model is a plan for a database design.

Answer

true

Question 2

The method of constructing data models used in the text is the extended entity-relationship (E-R) model.

Answer

true

Question 3

An entity instance is an occurrence of a particular entity.

Answer

true

Question 4

An identifier of an entity instance is one or more attributes that name or identify entity instances.

Answer

true

Question 5

In E-R modeling, an attribute describes the characteristics of an entity.

Answer

true

Question 6

In E-R modeling, entities within an entity class may have different attributes.

Answer

true

Question 7

Entities can be associated with one another in relationships.

Answer

true

Question 8

The Information Engineering (IE) model created by James Martin is often referred to as the IE Crowe’s Foot model.

Answer

true

Question 9

A principal difference between an entity and a table is that you can express a relationship between entities without using foreign keys.

Answer

true

Question 10

The notation 1:N shows a relationship's maximum cardinalities.

Answer

true

Question 11

Relationships are classified by their cardinality.

Answer

true

Question 12

In an E-R model, the three types of maximum cardinality are 1:1, 1:N, and N:M.

Answer

true

Question 13

In a 1:N relationship, the term parent refers to the N side of the relationship.

Answer

true

Question 14

An entity's minimum cardinality in a relationship indicates whether or not an entity must participate in the relationship.

Answer

true

Question 15

ID-dependent entities are associated by a nonidentifying relationship.

Answer

true

Question 16

ID-dependent entities are a common type of weak entity.

Answer

true

Question 17

An exclusive subtype pattern has one supertype entity that relates to one or more subtype entities.

Answer

true

Question 18

Entities with an IS-A relationship should have the same identifier.

Answer

true

Question 19

Relationships between supertypes and subtypes are called IS-A relationships.

Answer

true

Question 20

Which of the following is not a key element of an E-R model?

Accepted Answer

Objects

Answer

Relationships

Answer

Entities

Answer

Attributes

Question 21

An occurrence of a particular entity is called an ________.

Accepted Answer

entity instance

Answer

entity class

Answer

entity relationship

Answer

entity attribute

Question 22

The characteristics of a thing are described by its ________.

Accepted Answer

attributes

Answer

identifiers

Answer

entities

Answer

objects

Question 23

Which of the following is not a common variant of the E-R model?

Accepted Answer

Object-oriented

Answer

IE Crow's Foot

Answer

IDEF1X

Answer

UML

Question 24

Minimum cardinality refers to ________.

Accepted Answer

the number of entity instances that must participate in a relationship

Answer

the most instances of one entity class that can be involved in a relationship with one instance of another entity class

Answer

the number of entity classes involved in a relationship

Answer

whether or not an entity is a weak entity

Question 25

In a minimum cardinality, minimums are generally stated as ________.

Accepted Answer

0 or 1

Answer

1 or N

Answer

M or N

Answer

one or many

Question 26

A circle across the relationship line near an entity indicates ________.

Accepted Answer

a minimum cardinality of "optional"

Answer

a maximum cardinality of "zero"

Answer

a maximum cardinality of "one"

Answer

a minimum cardinality of "required"

Question 27

Supertype/subtype entities are said to have a(n) ________ relationship.

Accepted Answer

IS-A

Answer

HAS-A

Answer

recursive

Answer

redundant

Question 28

When creating a relational database design from E-R diagrams, first create a relation for each relationship.

Answer

true

Question 29

When creating a table in the relational database design from an entity in the extended E-R model, the attributes of the entity become the rows of the table.

Answer

true

Question 30

The ideal primary key is short, numeric, and fixed.

Answer

true

Question 31

The values of a surrogate key have no meaning to the users.

Answer

true

Question 32

A null value is an attribute value that has been set to zero.

Answer

true

Question 33

A data constraint is a limitation on data values.

Answer

true

Question 34

A foreign key is a key that does not belong in any table.

Answer

true

Question 35

To represent an N:M relationship in a relational database design, an intersection table is created.

Answer

true

Question 36

To represent an N:M relationship in a relational database design, in essence it is reduced to two 1:N relationships.

Answer

true

Question 37

An intersection table is always ID-dependent on both of its parent tables.

Answer

true

Question 38

Association tables sometimes connect more than two entities.

Answer

true

Question 39

Referential integrity constraints should disallow adding a new row to a child table when the foreign key does not match a primary key value in the parent table.

Answer

true

Question 40

A referential integrity constraint policy that insures that all rows containing a foreign key value in a table are eliminated from the table when the row containing the corresponding primary key value in a parent table is eliminated from the database is called cascading deletes.

Answer

true

Question 41

The first step in transforming an extended E-R model into a relational database design is to ________.

Accepted Answer

create a table for each entity

Answer

create a table for each relationship

Answer

evaluate the entities against the normalization criteria

Answer

remove any recursive relationships

Question 42

Each attribute of an entity becomes a(n) ________ of a table.

Accepted Answer

column

Answer

primary key

Answer

foreign key

Answer

alternate key

Question 43

In a relational database design, all relationships are expressed by ________.

Accepted Answer

creating a foreign key

Answer

creating a primary key

Answer

creating a supertype

Answer

creating a subtype

Question 44

To represent a one-to-many relationship in a relational database design, ________.

Accepted Answer

the key of the parent is placed as a foreign key into the child

Answer

the key of the child is placed as a foreign key into the parent

Answer

an intersection table must be created

Answer

the key of the table on the "many" side is placed in the table on the "one" side

Question 45

Many-to-many relationships are represented by ________.

Accepted Answer

an intersection table which has 1:N relationships with the two tables

Answer

two tables with an M:N relationship

Answer

two tables with a 1:N relationship

Answer

an intersection table which has M:N relationships with the two tables

Question 46

A referential integrity constraint policy that guarantees that a row in a parent table always has a required entry in a child table ________.

Accepted Answer

Both A and B are correct

Answer

is known as a minimum cardinality enforcement action

Answer

needs to be documented by the database development team

Answer

is enforced in most DBMS products

Question 47

A referential integrity constraint policy that insures that foreign key values in a table are correctly maintained when there is a change to the primary key value in the parent table is called ________.

Accepted Answer

cascading updates

Answer

incremental updates

Answer

incremental deletes

Answer

cascading deletes

Question 48

The CONSTRAINT keyword is used to define one of several types of constraints.

Answer

true

Question 49

The CONSTRAINT keyword can be used in conjunction with the SQL keywords PRIMARY KEY and FOREIGN KEY.

Answer

true

Question 50

The UNIQUE keyword is used to define alternate keys.

Answer

true

Question 51

The MODIFY keyword is used to change the structure, properties or constraints of a table.

Answer

true

Question 52

The ALTER keyword is used to change the structure, properties or constraints of a table.

Answer

true

Question 53

Data values to be added to a table are specified by using the VALUES clause.

Answer

true

Question 54

One or more rows can be added to a table by using the INSERT statement.

Answer

true

Question 55

Rows in a table can be changed by using the UPDATE statement.

Answer

true

Question 56

An SQL virtual table is called a view.

Answer

true

Question 57

SQL views can be used to hide columns.

Answer

true

Question 58

SQL views are updatable when the view is based on a single table with no computed columns, and all non-null columns are present in the view.

Answer

true

Question 59

Which SQL keyword is used to name a new table and describe the table's columns?

Accepted Answer

CREATE

Answer

SET

Answer

SELECT

Answer

ALTER

Question 60

Which SQL keyword is used to impose restrictions on a table, data or relationship?

Accepted Answer

CONSTRAINT

Answer

SET

Answer

CREATE

Answer

SELECT

Question 61

Given the SQL statement:
	CREATE TABLE SALESREP (
	SalesRepNo	int	NOT NULL,
	RepName	char(35)	NOT NULL,
	HireDate	date	NOT NULL,

CONSTRAINT	SalesRepPK	PRIMARY KEY (SalesRepNo),
	CONSTRAINT	SalesRepAK1	UNIQUE (RepName)
	);

We know that ________.

Accepted Answer

RepName is a candidate key

Answer

RepName is the primary key

Answer

RepName is a foreign key

Answer

RepName is a surrogate key

Question 62

Which SQL keyword is used to change the structure, properties or constraints of a table?

Accepted Answer

ALTER

Answer

SET

Answer

CREATE

Answer

SELECT

Question 63

Which SQL keyword is used to delete a table's structure?

Accepted Answer

DROP

Answer

DELETE

Answer

DISPOSE

Answer

ALTER

Question 64

Which SQL keyword is used to change the values of an entire column?

Accepted Answer

SET

Answer

CHANGE

Answer

INSERT

Answer

SELECT

Database Design & Implementation Final Exam

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