Deck 7: Data Modeling With Entity Relationship Diagrams

Question 1

The Crow's Foot model is less implementation-oriented than the Chen model.

Answer 1

False

Question 2

Attributes are types of entities.

Answer 2

False

Question 3

The ER diagram represents the conceptual database as viewed by the end user.

Answer 3

True

Question 4

An ERM is dependent on the database type.

Question 5

In an ER diagram, primary keys are usually bolded.

Question 6

The DBMS can easily handle multivalued attributes.

Question 7

In both the Chen and Crow's Foot models, an entity is represented with a rectangle containing the entity's name.

Question 8

All simple attributes are also single-valued.

Question 9

In the Chen model, a multivalued attribute is connected to the owning entity with a double line.

Question 10

The word "entity" in the ER model corresponds to a table.

Question 11

Attributes have a domain that specifies the data type of the attribute.

Question 12

The ER model refers to a specific table row as an entity instance.

Question 13

In the original Chen model, each attribute is represented using an oval with the attribute name connected to the entity with a line.

Question 14

Derived attributes are stored in a special database table.

Question 15

The ER model refers to a specific table row as an entity occurrence.

Question 16

Ideally, a primary key is composed of several attributes.

Question 17

A composite identifier is a primary key composed of more than one attribute.

Question 18

Attributes cannot share a domain.

Question 19

All attributes are either simple or composite.

Question 20

Software vendors have adopted the Chen representation because of its compact representation.

Question 21

Some ____ database modeling concepts can be expressed only using the Chen notation.

A) developmental
B) conceptual
C) actual
D) specific

Question 22

In Chen notation, there is no way to represent cardinality.

Question 23

A ____ attribute can be further subdivided to yield additional attributes.

A) composite
B) simple
C) single-valued
D) multivalued

Question 24

The ____ attribute(s) make up the primary key in the table definition: CLASS (CRS_CODE, CLASS_SECTION, CLASS_TIME, CLASS_ROOM, PROF_NUM)

A) CRS_CODE
B) CLASS_SECTION
C) CRS_CODE and CLASS_SECTION
D) There is no primary key

Question 25

A ____ attribute is one that cannot be subdivided.

A) composite
B) simple
C) single-valued
D) multivalued

Question 26

A ____ identifier is composed of more than one attribute.

A) primary
B) foreign
C) composite
D) domain

Question 27

A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity.

Question 28

A relationship is identified by a name that describes the relationship.

Question 29

In an ER diagram, primary keys are indicated by ____.

A) bolding
B) italics
C) underlining
D) a special font

Question 30

Connectivities and cardinalities are established by business rules.

Question 31

The ERD represents the ____ database as viewed by the end user.

A) condensed
B) physical
C) logical
D) conceptual

Question 32

Ideally, an entity identifier is composed of ____ attribute(s).

A) zero
B) one
C) two
D) six

Question 33

Relationships operate only in one direction.

Question 34

The set of possible values for an attribute is a ____.

A) domain
B) range
C) set
D) key

Question 35

A recursive relationship is one in which a relationship can exist between occurrences of the same entity set

Question 36

A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship.

Question 37

Cardinality expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity.

Question 38

You should always load data from the 1 side of a 1:M relationship.

Question 39

The existence of a mandatory relationship indicates that the minimum cardinality is 0 or 1 for the mandatory entity.

Question 40

Attributes may share a ____.

A) name
B) domain
C) location
D) table

Question 41

A ____ should be a derived attribute.

A) person's name
B) person's age
C) person's social security number
D) person's phone number

Question 42

A relationship is an association between ____.

A) objects
B) entities
C) databases
D) fields

Question 43

The Crow's foot symbol with two parallel lines indicates ____ cardinality.

A) (0,N)
B) (1,N)
C) (1,1)
D) (0,1)

Question 44

In the ERD, cardinality is indicated using the ____ notation.

A) (max, min)
B) (min, max)
C) [min ... max]
D) {min|max}

Question 45

A ____ relationship exists when an association is maintained within a single entity.

A) unary
B) ternary
C) binary
D) weak

Question 46

A ____ relationship exists when two entities are associated.

A) unary
B) binary
C) ternary
D) weak

Question 47

Knowing the ____ number of entity occurrences is very helpful at the application software level.

A) maximum
B) minimum
C) approximate
D) maximum and minimum

Question 48

A ____ attribute can have only one value.

A) composite
B) simple
C) single-valued
D) multivalued

Question 49

Another word for existence-independent is ____.

A) weak
B) alone
C) unary
D) strong

Question 50

When the PK of one entity does not contain the PK of a related entity, the relationship is ____.

A) missing
B) weak
C) strong
D) neutral

Question 51

Although the conceptual model can handle ____ relationhips and multivalued attribues, you should not implement them in the RDBMS.

A) 1:1
B) M:N
C) 1:M
D) 1:N

Question 52

If an entity can exist apart from one or more related entities, it is said to be ____-independent.

A) existence
B) relationship
C) business
D) weak

Question 53

Some attributes are classified as ____.

A) simple
B) complex
C) defined
D) grouped

Question 54

An entity is said to be ____-dependent if it can exist in the database only when it is associated with another related entity occurrence.

A) existence
B) relationship
C) business
D) weak

Question 55

The existence of a(n) ____ relationship indicates that the minimum cardinality is at least 1 for the mandatory entity.

A) mandatory
B) optional
C) multivalued
D) single-valued

Question 56

____ attributes can have many values.

A) Composite
B) Simple
C) Single-valued
D) Multivalued

Question 57

A ____ entity has a primary key that is partially or totally derived from the parent entity in the relationship.

A) strong
B) weak
C) business
D) relationship

Question 58

A derived attribute is indicated in the Chen model by a ____.

A) single line
B) dashed line
C) circle
D) double line

Question 59

The term "____" is used to label any condition in which one or more optional relationships exist.

A) participation
B) optionality
C) cardinality
D) connectivity

Question 60

A derived attribute ____.

A) must be stored physically within the database
B) need not be physically stored within the database
C) has many values
D) must be based on the value of three or more attributes

Question 61

If the focus is on data-retrieval speed, you might also be forced to include ____ attributes in the design, which would not ordinarily be done.

A) multivalued
B) composite
C) weak
D) derived

Question 62

The associative entity is also known as a ____ entity.

A) unary
B) weak
C) strong
D) composite

Question 63

The M:N relationship between STUDENT and CLASS must be divided into two 1:M relationships through the use of the ENROLL entity; the ENROLL entity is ____.

A) weak
B) strong
C) optional
D) mandatory

Question 64

Storing ____________________ attributes requires constant maintenance.

Question 65

____ relationships are most common.

A) Unary
B) Binary
C) Ternary
D) Higher-degree

Question 66

The following step occurs first in the process of building an ERD: ____.

A) Develop the initial ERD.
B) Create a detailed narrative of the organization's description of operations.
C) Identify the attributes and primary keys that adequately describe the entities.
D) Identify the business rules based on the description of operations.

Question 67

____________________ are characteristics of entities.

Question 68

If Tiny College had some departments that were classified as "research only," they would not offer courses; therefore, the COURSE entity would be ____ to the DEPARTMENT entity.

A) existence-dependent
B) independent
C) weak
D) optional

Question 69

The Crow's Foot model is more ____________________-oriented than the Chen model.

Question 70

If an employee within an EMPLOYEE entity has a relationship with itself, that relationship is known as a ____ relationship.

A) self
B) self-referring
C) looping
D) recursive

Question 71

Complex ____ requirements may dictate data transformations, and they may expand the number of entities and attributes within the design.

A) information
B) entity
C) design
D) processing

Question 72

A person's social security number would be an example of a(n) ____________________ attribute.

Question 73

A(n) ____ entity is composed of the primary keys of each of the entities to be connected.

A) associative
B) recursive
C) unary
D) binary

Question 74

A(n) ____________________ attribute need not be physically stored within the database.

Question 75

A(n) ____________________ attribute is an attribute that must have a value.

Question 76

The ____________________ refers to a specific table row as an entity instance.

Question 77

Instead of storing a person's age, it is better to store the date of birth and use the difference between that value and the system date as a(n) ____________________ attribute.

Question 78

A ____ relationship exists when three entities are associated.

A) unary
B) binary
C) ternary
D) weak

Question 79

The ERM forms the basis of a(n) ___________________________________.

Question 80

____________________ are underlined in an ER diagram.