6354126
Questão 1
Questão
1. The extended entity relationship model (EERM) is sometimes referred to as the ____.
Responda
-
A) entity relationship model
-
B) enhanced entity relationship model
-
C) entity clustering relationship model
-
D) extended entity relationship diagram
Questão 2
Questão
2. ____ is a generic entity type that is related to one or more entity subtypes.
Responda
-
A) A subtype discriminator
-
B) Inheritance
-
C) A specialization hierarchy
-
D) An entity super type
Questão 3
Questão
3. The ____ depicts the arrangement of higher-level entity super types (parent entities) and lower-level entity subtypes (child entities).
Responda
-
A) subtype discriminator
-
B) inheritance
-
C) specialization hierarchy
-
D) entity super type
Questão 4
Questão
4. Within a specialization hierarchy, every subtype can have ____ super type(s) to which it is directly related.
Responda
-
A) zero
-
B) only one
-
C) one or many
-
D) many
Questão 5
Questão
5. A specialization hierarchy can have ____ level(s) of super type/subtype relationships.
Responda
-
A) zero
-
B) only one
-
C) one or many
-
D) many
Questão 6
Questão
6. The property of ____ enables an entity subtype to inherit the attributes and relationships of the super type.
Responda
-
A) subtype discriminator
-
B) inheritance
-
C) specialization hierarchy
-
D) entity super type
Questão 7
Questão
7. One important inheritance characteristic is that all entity subtypes inherit their ____ key attribute from their super type.
Responda
-
A) primary
-
B) natural
-
C) foreign
-
D) surrogate
Questão 8
Questão
8. At the implementation level, the super type and its subtype(s) depicted in the specialization hierarchy maintain a ____ relationship.
Responda
-
A) self-referencing
-
B) 1:1
-
C) 1:M
-
D) M:N
Questão 9
Questão
9. A(n) ____ is the attribute in the super type entity that determines to which entity subtype each super type occurrence is related.
Responda
-
A) subtype discriminator
-
B) inheritance discriminator
-
C) specialization hierarchy
-
D) entity super type
Questão 10
Questão
10. The default comparison condition for the subtype discriminator attribute is the ____ comparison.
Responda
-
A) not equality
-
B) less than
-
C) greater than
-
D) equality
Questão 11
Questão
11. Non-overlapping subtypes are subtypes that contain a(n) ____ subset of the super type entity set.
Responda
-
A) entity
-
B) subtypes
-
C) unique
-
D) nonunique
Questão 12
Questão
12. Overlapping subtypes are subtypes that contain ____ subsets of the super type entity set.
Responda
-
A) entity
-
B) subtypes
-
C) unique
-
D) nonunique
Questão 13
Questão
13. Partial completeness is symbolized by ____.
Responda
-
A) a dotted line
-
B) two dashed lines
-
C) a circle over a single line
-
D) a circle over a double line
Questão 14
Questão
14. ____ is the bottom-up process of identifying a higher-level, more generic entity super type from lower-level entity subtypes.
Responda
-
A) Specialization
-
B) Generalization
-
C) Partial completeness
-
D) Total completeness
Questão 15
Questão
15. An entity cluster is formed by combining multiple interrelated entities into ____.
Responda
-
A) a single abstract entity object
-
B) multiple abstract entity object
-
C) a single entity object
-
D) multiple entity objects
Questão 16
Questão
16. The most important characteristic of an entity is its ____ key, used to uniquely identify each entity instance.
Responda
-
A) primary
-
B) natural
-
C) foreign
-
D) surrogate
Questão 17
Questão
17. A ____ key is a real-world, generally accepted identifier used to uniquely identify realworld objects.
Responda
-
A) primary
-
B) natural
-
C) foreign
-
D) surrogate
Questão 18
Questão
18. If one exists, a data modeler uses a ____ as the primary key of the entity being modeled.
Responda
-
A) foreign key
-
B) combination key
-
C) surrogate key
-
D) natural identifier
Questão 19
Questão
19. The primary key's main function is to uniquely identify a(n) ____ within a table.
Responda
-
A) attribute
-
B) entity instance or row
-
C) entity subtype
-
D) natural identifier
Questão 20
Questão
20. Composite primary keys are particularly useful as identifiers of composite entities, where each primary key combination is allowed only once in the ____relationship.
Responda
-
A) 0:1
-
B) 1:1
-
C) 1:M
-
D) M:N
Questão 21
Questão
21. The “____” characteristic of a primary key states the following: The PK must uniquely identify each entity instance. A primary key must be able to guarantee unique values. It cannot contain nulls.
Responda
-
A) unique values
-
B) nonintelligent
-
C) preferably single-attribute
-
D) security complaint
Questão 22
Questão
22. The “____” characteristic of a primary key states the following: The selected primary key must not be composed of any attribute(s) that might be considered a security risk or violation. For example, using a Social Security number as a PK in an EMPLOYEE table is not a good idea.
Responda
-
A) unique values
-
B) nointelligent
-
C) preferably single-attribute
-
D) security complaint
Questão 23
Questão
23. The “____” characteristic of a primary key states the following: The PK should not have embedded semantic meaning. An attribute with embedded semantic meaning is probably better used as a descriptive characteristic of the entity rather than as an identifier.
Responda
-
A) unique values
-
B) nonintelligent
-
C) preferably single-attribute
-
D) security complaint
Questão 24
Questão
24. Surrogate primary keys are especially helpful when there is no ____ key.
Responda
-
A) primary
-
B) natural
-
C) foreign
-
D) composite
Questão 25
Questão
25.____ keys work with primary keys to properly implement relationships in the relational model.
Responda
-
A) foreign
-
B) composite
-
C) natural
-
D) surrogate
Questão 26
Questão
26. The preferred placement for a foreign key when working with a 1:1 relationship is to ____.
Responda
-
A) use the same primary key for both entities
-
B) create a bridge entity
-
C) place a foreign key in one of the entities
-
D) place a foreign key in both entities
Questão 27
Questão
27. When selecting a foreign key placement for a 1:1 relationship, place the PK of the entity on the mandatory side in the entity on the optional side as a FK, and make the FK mandatory when ____.
Responda
-
A) one side is mandatory and the other side is optional
-
B) one side participates in another relationship
-
C) both sides are optional
-
D) both sides are mandatory
Questão 28
Questão
28.____ data refer to data whose values change over time and for which you must keep a history of the data changes.
Responda
-
A) time-sensitive
-
B) time-variant
-
C) Historical
-
D) Change-based
Questão 29
Questão
29. A ____ occurs when you have one entity in two 1:M relationships to other entities, thus producing an association among the other entities that is not expressed in the model.
Responda
-
A) surrogate primary keys
-
B) time-variant data
-
C) design trap
-
D) fan trap
Questão 30
Questão
30.____ relationships occur when there are multiple relationship paths between related entities.
Responda
-
A) redundant
-
B) duplicated
-
C) time-variant
-
D) super type
Questão 31
Questão
31. According to the data modeling checklist, ____ should clearly define participation and cardinality rules.
Responda
-
A) entities
-
B) naming conventions
-
C) relationships
-
D) attributes
Quer criar seus próprios Quizzes gratuitos com a GoConqr? Saiba mais.