Test 1

Question 1

Disjoint subtypes are also known as ____ subtypes

Answer 1

non-overlapping

Question 2

Specialization is based on grouping ____ characteristics and relationships of the subtypes.

Answer 2

unique

Question 3

Usually, a data modeler uses a natural identifier as the ____ of the entity being modeled, assuming that the entity has a natural identifier

Answer 3

Primary key

Question 4

Unique values can be better managed when they are _____, because the database can use internal routines to implement a counter-style attribute that automatically increments values with the addition of each new row

Answer 4

numeric

Question 5

composite primary keys are particularly useful as identifiers of composite entities, where each Primary key combination is allowed____in the M:N relationship.

Answer 5

once

Question 6

Composite keys are useful as identifiers of weak entities, where the weak entity has a strong___ relationship with the parent entity.

Answer 6

identifying

Question 7

One practical advantage of a(n) ____key is that because it has no intrinsic meaning, values for it can be generated by the DBMS to ensure that unique values are always provided.

Answer 7

surrogate

Question 8

While using a surrogate key, one must ensure that the candidate key of the entity in question performs properly through the use of the “___” and “not null” constraints.

Answer 8

unique index

Question 9

From a data modeling point of view, ____ data refer to data who’s values change over time and for which one must keep a history of the data changes.

Answer 9

Time-variant

Question 10

The main concern with redundant relationships is that they remain____across the model

Answer 10

consistent

Question 11

____ are characteristics of entities

Answer 11

Attributes

Question 12

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

Answer 12

required

Question 13

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

Answer 13

single-valued

Question 14

a(n)____attribute need not be physically stored within the database

Answer 14

derived

Question 15

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

Answer 15

minimum

Question 16

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

Answer 16

primary key

Question 17

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

Answer 17

strong

Question 18

A weak entity must be ____-dependent

Answer 18

existence

Question 19

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

Answer 19

rectangle

Question 20

Participation is____ if one entity occurrence does not require a or responding entity occurrence in a particular relationship.

Answer 20

optional

Question 21

A table is also called a (n)____ because the relational model’s creator, E.F. Codd use the two terms as synonyms.

Answer 21

relation

Question 22

in a relational table, each column has a specific range of values known as the _____domain.

Answer 22

attribute

Question 23

in a relational model, ____ are also used to establish relationships among tables and to ensure the integrity of the data.

Answer 23

keys

Question 24

A primary key is the____key chosen to be the primary means by which rows of a table are uniquely identified.

Answer 24

candidate

Question 25

To avoid nulls, some designers use special codes, known as _____, to indicate the absence of some value.

Answer 25

flags

Question 26

The relational operators have the property of ____; that is, the use of relational algebra operators on existing relations (tables) produces new relations.

Answer 26

closure

Question 27

PRODUCT yields all possible pairs of rows from two tables, also known as the ____ product

Answer 27

Cartesian

Question 28

____ is the real power behind the relational database, allowing the use of independent tables linked by common attributes

Answer 28

JOIN

Question 29

A(n) ____links tables on the basis of an equality condition that compares specified columns of each table.

Answer 29

equijoin

Question 30

A(n) ____ provides a detailed description of all tables in the database created by the user and designer.

Answer 30

data dictionary

Question 31

___ is the result of processing raw data to reveal its meaning.

Answer 31

Information

Question 32

to reveal meaning, information requires____

Answer 32

context

Question 33

Information is produced by processing___.

Answer 33

data

Question 34

____ is data about data through which the end-user data are integrated and managed

Answer 34

Metadata

Question 35

A(n)_____ is a specific request issued to the DBMS for data manipulation.

Answer 35

query

Question 36

____databases focuses primarily on storing historical data and business metrics used exclusively for tactical or strategic decision making.

Answer 36

Analytical

Question 37

____ is a special language used to represent and manipulate data elements in a textual format.

Answer 37

XML(Extensible Markup Language)

Question 38

A(n) ____ is a spur-of-the-moment question

Answer 38

ad hoc query

Question 39

___exists when different versions of the same data appear in different places.

Answer 39

Data inconsistency

Question 40

____exists when the same data are stored unnecessarily at different places.

Answer 40

Data redundancy

Question 41

A process that focuses on data collection, storage, and retrieval. Common______ _____ functions include addition, deletion, modification, and listing

Answer 41

Data Management

Question 42

The process that yields the description of the database structure and determines the database componenets. ______ ______ is the second phase of the database life cycle

Answer 42

Database Design

Question 43

The collection of programs that manages the database

Answer 43

Database Management System (DBMS)

Question 44

51- ____ is used to reveal the meaning of data

Answer 44

Information

Question 45

68-In the relational model, _____ are important because they are used to insure that each row in a table is uniquely identifiable.

Answer 45

keys

Question 46

14- you can think of a table as a persistent representation of a logical relation

Answer 46

True

Question 47

A minimal superkey; that is, a key that does not contain a subset of attributes that is itself a superkey

Answer 47

Candidate key

Question 48

a primary key can be made up of one or more attributes

Answer 48

True

Question 49

88-an entity cluster is formed by combining multiple interrelated entities into _____

Answer 49

a single abstract entity

Question 50

75-Some attributes are classified as _____

Answer 50

simple

Question 51

A constraint that specifies whether each entity supertype occurrence must also be a member of at least one subtype. The ______ _______ can be partial or total.

Answer 51

Completeness constraint

Question 52

______means that some supertype occurrences might not be members of any subtype

Answer 52

Partial completeness

Question 53

___means that every supertype occurrence must be a member of at least one subtype.

Answer 53

Total completeness

Question 54

Aproblem that occurs when a realtionship is improperly or incompletely identified and therfor is represented in a waay that is not consistent with the real world. The most common ___ ___ is know as a fan trap

Answer 54

Design Trap

Question 55

The ____ ____ ____ resulting from the application of extended entity realitonsip concepts that proved additional semantic content in the er model

Answer 55

EER diagram

Question 56

A virtual entity type used to represent multiple entites and relationships in the erd and ___ ___ is formed by combining multiple interrelated entities into a single abstract entity in the final erd

Answer 56

entity cluster

Question 57

In a genreralization/ specialization hierarchy a subset of an entity supertyp. the ____ _____ contains the common characteriscs of entity subtypes

Answer 57

Entity supertype

Question 58

The result of adding more semantic constructs, such as entity supertypes, entity subtypes and entity clustering, to the original entity relationship model

Answer 58

Exentended entity relationship model (eerm)

Question 59

In the object-oreiented data model, the ability of an object to inherit the data sturctue and mehtods of theclasses above it in the class hierarchy

Answer 59

Inheritance

Question 60

A generallly accepted identifier for real0world objects. as its name implies an ___ ___ is a familiiar to end users and forms part of ther day-to-day business vocab

Answer 60

Natural Key

Question 61

in a generalization hierarrchy, a condition in which some supertype ocurrences might not be members of any subtype

Answer 61

Partial completeness

Question 62

the grouping of unique attribute into a sub types entity

Answer 62

Specialization

Question 63

an entity that coontains unique characteristics within a more broadly defined enntity known as a supertype

Answer 63

subtype

Question 64

___ ___ an er term for an association between two entities.

Answer 64

Binary relationship

Question 65

__ ____ an attribute that can be further subdivieded to yeild additional attributes

Answer 65

Composite attribute

Question 66

In er modley a key composed of more than one attribute.

Answer 66

Composite identifier

Question 67

a reltionship in which related entities are existence-dependent.

Answer 67

Identifying relatinoship

Question 68

A process based on repeitiion of steps and procedures

Answer 68

Iterative process

Question 69

a relationship in which one entity occurence must have a corresponding occurence in another entity

Answer 69

Mandatory participation

Question 70

and attribute that can ahve many values for a single entity occurence

Answer 70

Multivalued attributes

Question 71

A relationship in which the primary key of the dependent entity does not conatina the primary key of the related parent entity

Answer 71

Non-identifying relationship

Question 72

in er modelinng an attribute that does not requier a vlaue

Answer 72

optional attribute

Question 73

the organization of a relational database as described by the database administrator

Answer 73

Relational schema

Question 74

The number of entites or participatns assciated with a relationship

Answer 74

Relationship degree