Deck 3: The Enhanced E-R Model

Question 1

In the figure below, a student:

A) must be a graduate student, an undergraduate, a special student or some other type of student.
B) must be a graduate student or an undergraduate student.
C) must be at least a special student.
D) must be a doctoral student.

Answer 1

A

Question 2

The process of defining one or more subtypes of a supertype and forming relationships is called:

A) specialization.
B) generalization.
C) creating discord.
D) selecting classes.

Answer 2

A

Question 3

In the figure below, which of the following apply to both OUTPATIENTs and RESIDENT_PATIENTs?

A) Checkback_Date
B) Date_Discharged
C) Patient_Name
D) XML

Answer 3

C

Question 4

In the figure below, which of the following is a subtype of patient?

A) Outpatient
B) Physician
C) Bed
D) Date_Hired

Question 5

Given the following entities, which of the choices below would be the most complicated? Automobile: VIN, EngineSize, NumberOfDoors, NumberOfPassengers, FuelType, Transmission
SUV: VIN, EngineSize, NumberOfPassengers, NoWheelDrive, FuelType, Transmission
Truck: VIN, EngineSize, NoWheelDrive, FuelType, Transmission, Payload

A) Define one vehicle entity type to hold all entities.
B) Define a separate entity type for each entity.
C) Define a supertype called vehicle and make each of the entities subtypes.
D) Keep only the Truck entity type.

Question 6

Which of the following is a generic entity type that has a relationship with one or more subtypes?

A) Megatype
B) Supertype
C) Subgroup
D) Class

Question 7

The process of defining a more general entity type from a set of more specialized entity types is called:

A) generalization.
B) specialization.
C) normalization.
D) extrapolation.

Question 8

A(n) ________ constraint is a type of constraint that addresses whether an instance of a supertype must also be an instance of at least one subtype.

A) disjoint
B) overlap
C) completeness
D) weak

Question 9

The property by which subtype entities possess the values of all attributes of a supertype is called:

A) hierarchy reception.
B) class management.
C) multiple inheritance.
D) attribute inheritance.

Question 10

The following figure is an example of:

A) partial specialization.
B) completeness.
C) total specialization.
D) disjointness.

Question 11

The ________ rule states that an entity instance can simultaneously be a member of two (or more) subtypes.

A) disjoint
B) overlap
C) partial specialization
D) total specialization

Question 12

An attribute of the supertype that determines the target subtype(s) is called the:

A) determinant.
B) subtype decision.
C) disjoint indicator.
D) subtype discriminator.

Question 13

A ________ addresses whether an instance of a supertype may simultaneously be a member of two or more subtypes.

A) disjointness constraint
B) disjoint rule
C) partial specialization
D) total specialization

Question 14

The ________ rule specifies that an entity instance of a supertype is allowed not to belong to any subtype.

A) semi-specialization
B) total specialization
C) partial specialization
D) disjointness

Question 15

The ________ rule specifies that each entity instance of the supertype must be a member of some subtype in the relationship.

A) semi-specialization
B) total specialization
C) partial specialization
D) total convergence

Question 16

Which of the following is a completeness constraint?

A) Total specialization
B) Partial generalization
C) Total recall
D) Partial hybridization

Question 17

In the figure below, to which of the following entities are the entities "CAR" and "TRUCK" generalized?

A) Make
B) Vehicle
C) Model
D) Price

Question 18

The ________ rule specifies that an entity can be a member of only one subtype at a time.

A) exclusion
B) disjoint
C) removal
D) inclusion

Question 19

Subtypes should be used when:

A) there are attributes that apply to some but not all instances of an entity type.
B) supertypes relate to objects outside the business.
C) the instances of a subtype do not participate in a relationship that is unique to that subtype.
D) a recursive relationship is needed.

Question 20

In the figure below, the patient must be either an outpatient or a resident patient. This is an example of the ________ rule.

A) disjoint
B) specialization
C) generalization
D) overlap

Question 21

The subtype discriminator in the figure below is:

A) Part_Type.
B) Part_No.
C) Manufactured Part.
D) Location.

Question 22

The figure below is an example of a(n):

A) supertype/subtype hierarchy.
B) hierarchical data model.
C) entity cluster.
D) column cluster.

Question 23

Packaged data models:

A) are ready to use right out of the box.
B) require customization.
C) allow partial specialization.
D) cannot be used for most applications.

Question 24

All of the following are advantages of packaged data models EXCEPT:

A) packaged data models can be built using proven components evolved from cumulative experiences.
B) projects take less time and cost less.
C) the data model is easier to evolve.
D) more one-to-one relationships give the data model more flexibility.

Question 25

Using a packaged data model, projects take less time and cost because:

A) less personnel are required.
B) essential components and structures are already defined.
C) there is more time taken to model the enterprise.
D) packaged data models only run in Oracle.

Question 26

In a supertype/subtype hierarchy, subtypes that are lower in the hierarchy inherit attributes from not only their immediate supertype but from all ________ in the hierarchy.

A) subtypes
B) supertypes
C) constraints
D) dimensions

Question 27

The subtype discriminator is a composite attribute when there is a(n):

A) overlap rule.
B) disjoint rule.
C) partial specialization.
D) full specialization.

Question 28

In a supertype/subtype hierarchy, each subtype has:

A) only one supertype.
B) many supertypes.
C) at most two supertypes.
D) at least one subtype.

Question 29

Which of the following statements is true about the figure shown below?

A) A rental unit must be either an apartment or a house, and cannot be both at the same time.
B) A rental unit can be an apartment, house or just a rental unit; it may not be more than one at the same time.
C) A rental unit must be either an apartment or a house, and could be both.
D) A rental unit can be an apartment, a house or just a rental unit. It could be both an apartment and a house at the same time.

Question 30

A generic or template data model that can be reused as a starting point for a data modeling project is called a(n):

A) packaged data model.
B) universal data model.
C) enterprise data model.
D) collection data model.

Question 31

The following figure shows a:

A) disjoint constraint.
B) completeness constraint.
C) supertype/subtype hierarchy.
D) spindle constraint.

Question 32

Which of the following is true of packaged data models?

A) Relationships are connected to the highest-level entity type in an order that makes sense.
B) All subtype/supertype relationships follow the total specialization and disjoint rules.
C) No entities on the many sides of a relationship can be weak.
D) All weak entities are considered strong.

Question 33

Which statement is true about the following diagram?

A) A person can only be a faculty, student, or staff.
B) A student can be both an undergraduate and a graduate student at the same time.
C) All attributes of person and student are inherited by undergraduate.
D) All attributes of graduate are inherited by person.

Question 34

Which of the following statements is true about the figure shown below?

A) A rental unit must be either an apartment or a house, and cannot be both at the same time.
B) A rental unit can be an apartment, house or just a rental unit; it may not be more than one at the same time.
C) A rental unit must be either an apartment or a house, and could be both.
D) A rental unit can be an apartment, a house or just a rental unit. It could be both an apartment and a house at the same time.

Question 35

The following diagram shows:

A) total specialization.
B) partial specialization.
C) the overlap rule.
D) subtype discriminator.

Question 36

An entity cluster is:

A) a formal method for specifying attributes of related entities.
B) a set of one or more entity types and associated relationships grouped into a single abstract entity type.
C) a useful way to present data for a small and fairly simple organization.
D) a way of developing more granular views of the data model.

Question 37

Which of the following statements is true about the figure shown below?

A) A rental unit must be either an apartment or a house, and cannot be both at the same time.
B) A rental unit can be an apartment, house or just a rental unit; it may not be more than one at the same time.
C) A rental unit must be either an apartment or a house, and could be both.
D) A rental unit can be an apartment, a house or just a rental unit. It could be both an apartment and a house at the same time.

Question 38

The following figure shows an example of:

A) the disjoint rule.
B) the completeness rule.
C) the underdog rule.
D) the overlap rule.

Question 39

An entity cluster can be formed by:

A) deleting a supertype and its subtype.
B) combining metadata.
C) combining a strong entity and its weak entities.
D) deleting metadata.

Question 40

Which of the following statements is true about the figure shown below?

A) A rental unit must be either an apartment or a house, and cannot be both at the same time.
B) A rental unit can be an apartment, house or just a rental unit; it may not be more than one at the same time.
C) A rental unit must be either an apartment or a house, and could be both.
D) A rental unit can be an apartment, a house or just a rental unit. It could be both an apartment and a house at the same time.

Question 41

The third step in the data modeling process with a packaged data model is:

A) rename identified data elements.
B) rename relationships.
C) map data to be used from package to data in current databases.
D) interview users.

Question 42

Specialization is the reverse of generalization.

Question 43

The following figure is an example of total specialization.

Question 44

A subtype is a generic entity that has a relationship with one or more entities at a lower level.

Question 45

Supertype/subtype relationships should not be used when the instances of a subtype participate in no relationships which are unique to that subtype.

Question 46

All of the following are steps to using a packaged data model EXCEPT:

A) identify the parts of the data model that apply to your data modeling situation.
B) utilize all business rules that come with the packaged data model.
C) rename the identified data elements.
D) map data to be used in packages with existing data in the current databases.

Question 47

The overlap rule specifies that if an entity instance of the supertype is a member of one subtype, it can simultaneously be a member of two (or more) subtypes.

Question 48

When the total specialization rule is set for a supertype/subtype relationship, one could roughly compare the supertype to an abstract class in object-oriented programming.

Question 49

Generalization is a top-down process.

Question 50

A member of a subtype does NOT necessarily have to be a member of the supertype.

Question 51

When identifying the parts of the packaged data model that apply to your organization, one should first start with:

A) entities.
B) attributes.
C) primary keys.
D) relationships.

Question 52

One of the major challenges in data modeling is to recognize and clearly represent entities that are almost the same.

Question 53

An entity instance of a subtype represents the same entity instance of the supertype.

Question 54

A completeness constraint may specify that each entity of the supertype must be a member of some subtype in the relationship.

Question 55

The total specialization rule states that an entity instance of a supertype is allowed not to belong to any subtype.

Question 56

The most important challenge of customizing a purchased data model is:

A) getting user buy-in.
B) determining the business rules that will be established through the data model.
C) implementation.
D) user training.

Question 57

In packaged data models, strong entities always have ________ between them.

A) weak entities
B) 1:1 relationships
C) 1:M relationships
D) M:N relationships

Question 58

A good method for identifying inconsistencies and finding hidden meaning in the customized purchased data model is:

A) data analysis.
B) data volume usage analysis.
C) user interviews.
D) data profiling.

Question 59

In packaged data models, all subtype/supertype relationships follow the ________ and ________ rules.

A) partial specialization; disjoint
B) total specialization; disjoint
C) total specialization; overlap
D) partial specialization; overlap

Question 60

The disjoint rule specifies that if an entity instance of the supertype is a member of one subtype, it MUST simultaneously be a member of another subtype.

Question 61

Entity clustering is a methodology for grouping one or more entity types and associated relationships into a single abstract entity type.

Question 62

In the figure shown below, a rental unit has to be either a house or an apartment.

Question 63

In the figure shown below, a rental unit can be both a house and an apartment.

Question 64

In the figure shown below, a rental unit can be both an apartment and a house but must be at least one.

Question 65

An entity cluster can have a relationship with another entity cluster much the same way that an entity can have a relationship with another entity.

Question 66

Subtypes at the lowest level of a hierarchy do not inherit attributes from their ancestors.

Question 67

An entity cluster should focus on some area of interest to some community of users, developers, or managers.

Question 68

In the figure shown below, there could be an instance of a rental unit that is neither an apartment nor a house.

Question 69

In a supertype/subtype hierarchy, attributes are assigned at the highest logical level that is possible in the hierarchy.

Question 70

A subtype can become a supertype if the subtype has other subtypes beneath it.

Question 71

Packaged data models are meant to be customized.

Question 72

Packaged data models cause projects to take more time to build.

Question 73

The following figure is an example of the overlap rule.

Question 74

There are three separate discriminators in the following diagram because of the overlap rule.

Question 75

Packaged data models use an entity type to store union data.

Question 76

When subtypes are overlapping, an additional field must be added to the supertype to act as a discriminator.

Question 77

The following diagram is an example of a supertype/subtype hierarchy.

Question 78

A universal data model is a generic or template data model that can be reused as a starting point for a data modeling project.

Question 79

Regardless of the business situation, a member of the supertype is always a member of more than one subtype.

Question 80

Packaged data models can be developed using proven components.