Deck 4: Entity Relationship Ermodeling

Question 1

The Crow's Foot notation easily identifies multivalued attributes.

Answer 1

False

Question 2

Composite attributes make it easier to facilitate detailed queries.

Answer 2

False

Question 3

An entity in the entity relationship model corresponds to a table in the relational environment.

Answer 3

True

Question 4

The entity relationship model (ERM)is dependent on the database type.

Question 5

In the original Chen notation,each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line.

Question 6

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

Question 7

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

Question 8

In the entity relationship model,a table row corresponds to an entity instance.

Question 9

The Crow's Foot notation is less implementation­oriented than the Chen notation.

Question 10

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

Question 11

Connectivities and cardinalities are established by concise statements known as business rules.

Question 12

Unary relationships are common in manufacturing industries.

Question 13

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

Question 14

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

Question 15

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

Question 16

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

Question 17

In implementation terms,an entity is existence-dependent if it has a mandatory primary key.

Question 18

Relationships between entities always operate in one direction.

Question 19

Referential integrity and participation are both bidirectional,meaning that they must be addressed in both directions along a relationship.

Question 20

In a 1:M relationship,to avoid the possibility of referential integrity errors,the data of the "1" side must be loaded first.

Question 21

The decision to store attributes in database tables depends on the processing requirements and the constraints placed on a particular application.

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

Question 22

The notation of entity-relationship modelling can be used for both conceptual and implementation modelling.

A)Bachman
B)UML
C)Chen
D)Crow's Foot

Question 23

A(n)is the set of possible values for a given attribute.

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

Question 24

If an entity can exist apart from all of its related entities,then it is existence-independent,and it is referred to as a(n)entity.

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

Question 25

The entity relationship diagram (ERD)represents the database as viewed by the end user.

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

Question 26

A relationship is an association between .

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

Question 27

To implement a small database,a database designer must know the "1" and the "M" sides of each relationship and whether the relationships are mandatory or optional.

Question 28

The process of database design is a sequential process.

Question 29

Knowing the minimum and maximum number of occurrences is very helpful at the application software level.

A)object
B)attribute
C)data
D)entity

Question 30

The conceptual model can handle relationships and multivalued attributes.

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

Question 31

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

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

Question 32

A derived attribute is indicated in the Chen notation by a that connects the attribute and an entity.

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

Question 33

In the entity relationship diagram (ERD),cardinality is indicated using the notation,where max is the maximum number of associated entities and min represents the minimum number of associated entities.

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

Question 34

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

A)Connectivity
B)Relationship
C)Dependence
D)Cardinality

Question 35

The existence of a(n)entity indicates that its minimum cardinality is zero.

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

Question 36

A attribute is one that cannot be subdivided.

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

Question 37

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)data

Question 38

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)child

Question 39

A attribute can be further subdivided to yield additional attributes.

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

Question 40

When the specific cardinalities are not included on the diagram in Crow's Foot notation,cardinality is implied by the use of _____.

A)symbols
B)attributes
C)images
D)tables

Question 41

The entity relationship model uses the associative entity to represent a(n)relationship between two or more entities.

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

Question 42

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

Question 43

In organizations that generate large number of transactions,are often a top priority in database design.

A)relationships among entities
B)logical design standards
C)naming conventions
D)high processing speeds

Question 44

When using the Crow's Foot notation,the associative entity is indicated by relationship lines between the parents and the associative entity.

A)dotted
B)double
C)triple
D)solid

Question 45

A relationship exists when three entities are associated.

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

Question 46

The concept of relationship strength is based on how the of a related entity is defined.

Question 47

When indicating cardinality,the first value represents the number of associated entities.

Question 48

are underlined in an ER diagram.

Question 49

A person's Social Security number would be an example of a(n)attribute.

Question 50

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

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

Question 51

To simplify the conceptual design,most higher-order relationships are decomposed into appropriate equivalent relationships whenever possible.

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

Question 52

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

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

Question 53

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 54

A(n)relationship is also known as an identifying relationship.

Question 55

A relationship is difficult to establish if only one side of the relationship is known.

Question 56

If Tiny College has some departments that are classified as "research only" and do not offer courses,the COURSE entity of the college database would be the DEPARTMENT entity.

A)existence-dependent on
B)independent of
C)mandatory for
D)optional to

Question 57

The first step in building an entity-relationship diagram (ERD)is .

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

Question 58

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 59

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

Question 60

are characteristics of entities.

Question 61

Explain multivalued attributes with the help of examples.How are multivalued attributes indicated in the Chen Entity Relationship model?

Question 62

A(n)process is based on repetition of processes and procedures.

Question 63

What is a ternary relationship? Provide some business rules examples that specify the need for a ternary or higher- order relationship.

Question 64

In Crow's Foot notation,an optional relationship between entities is shown by drawing a(n)on the side of the optional entity.

Question 65

not only helps database designers to stay on track during the design process,it also enables them to pick up the design thread when the time comes to modify the design.

Question 66

Failure to understand the distinction between mandatory and optional in relationships might yield designs in which awkward (and unnecessary)temporary rows (entity instances)must be created just to accommodate the creation of required entities.

Question 67

A weak entity must be -dependent.

Question 68

What is a weak relationship? Provide an example.

Question 69

Identifying the attributes of entities helps in the better understanding of among entities.

Question 70

Participation is if one entity occurrence does not require a corresponding entity occurrence in a particular relationship.

Question 71

Explain mandatory participation in an entity relationship.

Question 72

The Crow's Foot notation depicts the strong relationship with a(n)line between the entities.

Question 73

A relationship indicates the number of entities or participants associated with a relationship.

Question 74

The Chen notation identifies a weak entity by using a double-walled entity .

Question 75

Explain recursive relationships with the help of an example.