Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

database > test review > Flashcards

test review Flashcards

1
Q

true or false: good decisions require good information derived from raw date

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where is data best stored?

A

in a database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

t or f: understanding file system characteristics is not important?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

when is the database used?

A

almost everywhere like management, research, and administration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

true or false: it is important to understand how database work and interact with other apps?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is information?

A

is the result of processing raw data to reveal meaning.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

t or f: Raw data must be formatted for storage, processing, and presentation?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

t or f: data are the foundation of information, which is the bedrock of knowledge?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is data in relation to information?

A

data is the building block of information

information is produced by processing data.

information used to reveal the meaning of data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

why are accuracy, relevancy, and time information important?

A

for good decision-making.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is data management focused on?

A

proper generation, storage, and retrieving of data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a database?

A

shared, integrated computer structure that stores a collection of end-user data. metadata.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is end-user data?

A

raw facts of interest to end user.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is metadata?

A

data about data

it provides a description of data characteristics and relationships in data.

complements and expands value of data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is a database management system (DBMS)?

A

collection of programs

manages the structure and controls access to data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

t or f: DBMS is the intermediary between the user and the database?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

t or f: database structure stored as file collection?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

t or f: you can access files through the DBMS and many more?

A

false (only DBMS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

t or f: DBMS enables data to be shared?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

t or f: DBMS does not integrate many users’ views of the data?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the advantages of DBMS?

A

improve data sharing.
improve data security.
better data integration.
minimize data inconsistency.
improve data access.
improve decision-making.
increase end-user productivity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

the database can be classified according to the:

A

number of users
database location
expected type and extent of use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

t or f: single-user database supports one or more users at a time?

A

false (only one)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is a desktop database?

A

single user runs on PC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is the difference between a centralized database and distributed database?

A

centralized database located at a single site.

a distributed database is data distributes across several different sites.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is a data warehouse?

A

stores data used for tactical or strategic decisions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

types of data?

A

structured data: resulted from the formatting.
unstructured data: data exist in their original state
semistructured data: data have been processed to some extent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is an extensible markup language (XML)?

A

represents data elements in textual format.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what database does XML support?

A

semistructural XML data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

why is a database design important?

A

it focuses on the design of database structure used for end-user data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is the difference between a well-designed and a poorly-designed database?

A

well-designed: facilitates data management

poorly-designed: causes difficult to trace errors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

reasons for studying file systems?

A

complexity of database design is easier to understand

understanding it helps avoid problems with DBMS systems.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

t or f: the content of each file folder is not logically related?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is the difference between manual file systems and computerized file systems?

A

manual file systems served as a repository for small data collection.

computerized file systems are a data processing specialist in converting computer file structure from manual systems.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

t or f: as the number of files decreases, file systems evolve?

A

False (increases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

initially, what does a computer file system resemble?

A

manual systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

t or f: each file used its own application program to store, retrieve, and modify data?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what is the difference between data, field, record, and file?

A

data are raw facts that do not have a meaning or little meaning.

field is a character or group of characters that have a specific meaning.

record is a logically connected set of one or more fields that describe a person, place, or thing.

a file is a collection of related records.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

t or f: the ubiquitous use of personal productivity tools can introduce the same problems as the old file systems?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what is Microsoft excel?

A

widely used by business users and a database substitute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

t or f: file systems were not an improvement over the manual systems?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

how long were file systems were used?

A

more than two decates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

t or f: many problems are unique to file systems?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

t or f: even simple file system retrieval required extensive programming?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

summary of file system limitation contain?

A

requires extensive programming.
can not perform ad hoc queries.
system administration is complex and difficult.
difficult to make changes to existing structures.
security features are likely to be inadequate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what is structural dependence?

A

access to a file is dependent on its own structure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

t or f: all file system programs must be modified to conform to a new file structure?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what is structural independence?

A

change file structure without effecting data access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

what is data dependence?

A

data access changes when data storage characteristics change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is data independence?

A

data storage characteristics do not effect data access.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

t or f: practical significance of data dependence is different between logical and physical data?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

what is the difference between logical and physical format?

A

the logical format is how human views the data.

the physical format is how computers must work with data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

each program must contain?

A

lines specifying the opening of specific file types.

record specifications.

field definition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

t or f: file system structure does not make it difficult to combine data from multiple resources?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

t or f: organizational structure promotes storage of the same data in different locations?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

t or f: data stored in different locations are unlikely to be updated consistently?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

what is data redundancy?

A

same data stored unnecessarily in different locations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

what is data inconsistency?

A

different and conflicting versions of the same data occurs in different places.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what is data anomalies?

A

abnormalities when all changes in redundant data are not made correctly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

to avoid data anomalies you have to?

A

update anomalies
insertion anomalies
deletion anomalies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

t or f: most users lack the skill to properly design databases despite having multiple productivity tools available.

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

t or f: data modeling skills are not vital in the data design process?

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

t or f: good data modeling facilitates communication between designer, user, and developer?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

t or f: database system consists of logically related data stored in multiple logical data repository?

A

false, only one data repository

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

t or f: DBMS eliminates most of the file system’s problems?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what is the database system environment?

A

defines and regulates the collection, storage, management, and use of data.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

what are the five major parts of the database systems?

A

hardware
software
people
procedures
data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

what is the difference between software and hardware?

A

hardware is the physical device.

software is the programmed devices and there are three types of software required:

operating system software.
DBMS software.
application programs and utility software.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

who are the people in the database system?

A

all users of the database:

system and database admins
designers
system analysts and programmers
end-users

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

what are the procedures?

A

instructions and rules that govern the design and use of the database system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

what is the data?

A

the collection of facts stored in the database.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

t or f: database systems are created and managed at the same level of complexity?

A

false (at different levels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

t or f: database solutions must be cost-effective as well as tactically and strategically effective?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

why are most functions are transparent to end users?

A

cause it can only be achieved through the DBMS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

what does a data dictionary do?

A

DBMS stores definitions of data elements and relationships (metadata) in a data dictionary.

looks up required data component structures and relationships.

changes automatically recorded in the dictionary.

DBMS provides data abstraction and removes structural and data dependency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what does data storage management do?

A

DBMS creates and manages complex structures required for data storage

also stores related data entry forms, screen definition, record definition, etc

performance tuning

DBMS stores data in multiple physical files

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

what is performance tuning?

A

activities that makes the database perform more efficiently.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

what do data transformation and presentation do?

A

DBMS transforms data entered to conform to a required data structure.

DBMS transforms physically retrieved data to conform to the user’s expectations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

what does data security do?

A

DBMS creates a security system that enforces user privacy and security.

security rules determine which users can access the database, which items can be accessed, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

what does multiuser access control do?

A

DBMS uses sophisticated algorithms to ensure concurrent access does not effect integrity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

what do backup and recovery management do?

A

DBMS provides data backup and data recovery to ensure data safety and integrity.

it deals with recovery after a failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

what do backup and recovery management do?

A

DBMS provides data backup and data recovery to ensure data safety and integrity.

it deals with recovery after a failure

it is critical to preserving database integrity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

what does data integrity do?

A

promotes and enforces integrity rules

minimize redundancy
maximize consistency

data relationships stored in a data dictionary used to enforce integrity

integrity is especially important in a transaction-oriented database system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

what do database access languages and application programming interfaces do?

A

provides access through a query language

query language is a nonprocedural language

structure query language (SQL) is de facto query language

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

what do database communication interfaces do?

A

current DBMS accept end-user request via multiple different network environments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

what are the ways that communication is being accomplished?

A

end users generally answer query Qs by filling in screen forms through web browsers.

DBMS automatically publishes predefined reports on a web site.

DBMS connects to third party systems to distribute information via E-mail.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

what does a database system provides a framework in which strict procedures and standers enforced do?

A

role of human changes from programming to managing organizational resources.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

t or f: database system enables more sophisticated use of data?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

t or f: data structures create within the database and their relationship determine effectiveness?

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

what are the disadvantages of a database system?

A

increase cost

management complexity

maintain currency

vendor dependence

frequent update/replacement cycles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

chapter 2

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

the process that establishes need for and extent of information system. this is the def of?

A

system analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

the process of creating information system?

A

systems developement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

transforms data into information that forms basis for decision making?

A

applications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

usually, applications produce the following?

A

formal report
tabulation
graphic displays

96
Q

the applications are composed into two parts. what is it?

A

data
code

97
Q

performance depends on three factors, what is it?

A

DB design and implementation
application design and implementation
administrative procedures

98
Q

the process of DB design and implementation. this is the def of?

A

DB developement

99
Q

The implementation phase includes:

A

creating DB storage structure
loading data into the database
providing for data management

100
Q

what is SDLC stand for?

A

system development life cycle

101
Q

how phases are in the SDLC?

A

5
planning
analyzing
designing
implementation
maintenance

102
Q

the general overview of company and objectives. this is the def of?

A

planning

103
Q

assessment of flow and extent requirements consists of three Q’s and they are?

A

should the existing system be continued
should the existing system be modified
should the existing system be replaced

104
Q

studying and evaluating alternate solutions consists of?

A

tech aspects of hardware and software requirements

system cost

operation cost

105
Q

the problems defined during planning phases are examined in greater detail during the?

A

analysis

106
Q

t or f: analysis studies existing hardware and software

A

true

107
Q

some of the goals in the analysis stages are a better understanding of:

A

system function area
actual and potential problems
oppertunities

108
Q

the designer completes the design of system processes in which stage?

A

detailed system design

109
Q

t or f: detailed system design includes all necessary technical specifications?

A

true

110
Q

t or f: detailed system design are steps laid out for conversion from the old to the new system, and the training principles and methodologies are also planned

A

true

111
Q

why are the detailed system design submitted?

A

for management’s approval

112
Q

At which stage do the hardware, software, and application programs are installed?

A

implementation

113
Q

until when the cycle of coding, testing, and debugging continues?

A

until database is ready for delivery

114
Q

the database is created and the system is customized in which stage?

(creation of tables and views)
(user authorization)

A

implementation

115
Q

three types of maintenance activity:

A

corrective
adaptive
perfective

116
Q

what is CASE?

A

computer aided system engineering

117
Q

t or f: CASE produces worse systems within a reasonable amount of time and at a reasonable cost?

A

false

118
Q

t or f: CASE produced applications are structured,documented, and standardized

A

true

119
Q

how many phases are in the DBLC?

A

6
DB initial study
DB design
implementation and loading
testing and evalution
operation
maintenance and evolution

120
Q

what are the DB initial study’s overall purposes:

A

analyze company situation.
define problems and constraints
define objectives
define scope and boundries

121
Q

t or f: interactive and iterative processes required to complete the second phase of DBLC successfully?

A

false

122
Q

general conditions in which the company operates, its organizational structure, and its mission, this is the def of?

A

analyze the company situation

123
Q

t or f: the goal of the analyzing the company situation is to discover what company’s operational components are,how they function, and how they interact?

A

true

124
Q

defining problems and constraints are generated into three categories which are:

A

formal and informal information sources

finding precise answers is important

accurate problem definition does not always yield a situation.

125
Q

t or f: database system objectives must correspond to those envisioned by middle users?

A

false

126
Q

what are the Qs in the database’s initial study?

A

what is the proposed system’s initial objective?

will the system interface with other systems in the company?

will system share data with other systems or users?

127
Q

the extent of design according to operational requirements. this is the def of?

A

scope

128
Q

limits external to system. this is the def of?

A

boundaries

129
Q

necessary to concentrate on data characteristics required to build Db model?

A

DB design

130
Q

there are two views of data within system and they are?

A

business view

designer view

131
Q

this business view is about data as an information source?

A

business view

132
Q

this view is about data structure, access, and activity required to transform data into information?

A

designer view

133
Q

actually implementing all design specifications from the previous phase. this is the def of which step?

A

implementation and loading

134
Q

what are the steps of the implementation:

A

install DBMS

create database

load or convert the data

135
Q

created logical representations of computing resources independent of physical resources. this is the def of?

A

virtualization

136
Q

where do testing and evaluation occur?

A

in parallel with application programs

137
Q

t or f: DB tools used to prototype applications?

A

true

138
Q

if implementation fails to meet some system’s evaluation criteria, what should we do?

A

fine-tune specific to DBMS configuration parameters

modify physical or logical design

upgrade software or/and hardware platforms

139
Q

what is being enforced via proper use of primary, foreign key rules?

A

integrity

140
Q

types of backup and recovery after testing and evaluation:

A

full backup
differential backup
transaction backup

141
Q

once a database has passed evaluation stage, it is considered an?

A

operational

142
Q

t or f: the beginning of the operational phase starts the process of the system evolution

A

true

143
Q

t or f: problems are forseen during testing surface?

A

false

144
Q

solutions to the problems occurring in the operation phase include:

A

load-balancing software to distribute transactions amoung multiple computers

increase available cache

145
Q

in which stage is it required periodic maintenance?

A

maintenance and evolution

146
Q

t or f: preventing maintenance is for data recovery?

A

false

147
Q

t or f: corrective is for data recovery ?

A

true

148
Q

data modeling creates an abstract database structure. this is the def of?

A

conceptual design

149
Q

t or f: conceptual design represents real world objects?

A

true

150
Q

t or f: conceptual design doesn’t embody clear understanding of business and its funtional erea?

A

false

151
Q

how many steps is it required for the conceptual design?

A

4

152
Q

discover data element characteristics, this is the def of?

A

data analysis and requirements

153
Q

t or f: data analysis obtain its characteristics from the same location?

A

false (different locations)

154
Q

t or f: data analysis require thorough understanding of the company data types and their extent and uses?

A

true

155
Q

t or f: data analysis takes into account business rules?

A

true

156
Q

designer enforces standards in design documentation. this is the def of?

A

entity relationship modeling and normalization

157
Q

designer enforces standards in design documentation. this is the def of?

A

entity relationship modeling and normalization

158
Q

designer enforces standards in design documentation by?

A

use of diagram and symbols, documentation writing style, layout, other conventions

159
Q

business rules must be incorporated into?

A

conceptual model

160
Q

is a communications tool as well as a design blueprint?

A

ER model

161
Q

verified against proposed system processes. this is the def of?

A

data model verification

162
Q

revision of the original design by?

A

careful reevaluation of entities

detailed examination of attributes describing entities

163
Q

information system components that handle specific functions, this is the def of?

A

module

164
Q

portions of DB may reside in a different physical location. this is the def of?

A

distributed DB design

165
Q

a subset of a DB stored at a given location. this is the def of?

A

DB fregment

166
Q

t or f: distributed DB design processes accessing the database vary from one location to another?

A

true

167
Q

t or f: the designer must also develop data distribution and allocation strategies?

A

true

168
Q

critical to information system’s smooth operation. this is the def of?

A

DBMS software selection

169
Q

common factors effecting purchasing decisions:

A

cost
DBMS features tools
underlying model
portability
DBMS hardware requirements

170
Q

map conceptual design to a specific data model, this is the def of?

A

logical design

171
Q

t or f: logical design still independent of physical-level details?

A

true

172
Q

t or f: logical design translates software-independant conceptual model into software-dependant model

A

true

173
Q

five mapping steps involve:

A

strong entities
supertype/subtype relationships
weak entities (dependant on strong entities)
binary relationship
higher degree relationships

174
Q

t or f: all defined constraints must be supported by the logical data model?

A

true

175
Q

translation requires the definition of the ……. domains and appropriate constraints?

A

attributes

176
Q

t or f: all defined constraints must be supported by the logical data model

A

true

177
Q

t or f: special attention should be placed at this stage to ensure security is enforce, may have to consider security restrictiond at the same location?

A

false, different location

178
Q

all defined constrains must be supported by the logical data model. this is the def of?

A

the validate logical model integrity constrains

179
Q

validate logical model integrity constrains is to ensure:

A

all views can be resolved

security is enforced to ensure the privacy of the data

180
Q

final step in the logical design process?

A

validate the logical model against user requirements

181
Q

t or f: in the final step, validate logical model definitions against all end-user data,transaction,and security requirements

A

true

182
Q

process of selecting data storage and data access characteristics of the database. this is the def of:

A

physical design

183
Q

storage characteristics are function of:

A

device types supported by hardware

types of data access methods supported by system

DBMS

184
Q

t or f: physical design is more complex when data are distributed?

A

true

185
Q

designer must determine several attributes, they are:

A

data volume
data usage patterns

186
Q

define data storage organization in turn influence:

A

location and physical storage organization for each table

what indexes and types of indexes are to be used for each table

what views and the type views to be used on each table

187
Q

set of database privileges that could be assigned as a unit to a user or group. this is the def of:

A

DB role

188
Q

assign security controls by:

A

specific access rights on DB objects to a user or group of users

can also revoke during operation to assist with backups or maintenance events

189
Q

performance can be affected by characteristics and they are:

A

storage media

seek time

sector and block size

and more

190
Q

t or f: fine-tuning the DBMS and queries to ensure that they will meet end-user performance requirements?

A

true

191
Q

chapter 4

A
192
Q

t or f: relational DB model offers a logical view of data?

A

true

193
Q

view data logically rather than physically. this is the def of?

A

relational model

194
Q

structure and data independence. resembles a file collection. these are the the defs of?

A

table

195
Q

t or f: relational database is harder to understand than hierarchal and network models?

A

false

196
Q

t or f: logical view of relational DB is based on relation

A

true

197
Q

t or f: relation is not the same as a table

A

false

198
Q

two-dimensional structure composed of rows and columns, this is the def of?

A

table

199
Q

t or f: table is a persistent representation of logical relation

A

true

200
Q

t or f: a table contains group of related entities(entity set)?

A

true

201
Q

t or f: each row in a table must be uniquely identifiable?

A

true

202
Q

one or more attributes that determine other attributes, this is the def of?

A

key

203
Q

what is a key role based on?

A

determination

204
Q

t of f: if you know the value of attribute A, you can’t know the value of attribute B?

A

false

205
Q

Attribute B is functionally dependent on A if all rows that agree in value A also agree on value B, this is the def if?

A

functional dependence

206
Q

composed of more than one attribute. this is the def of?

A

composite key

207
Q

any attribute that is a part of a key?

A

key attribute

208
Q

any key that uniquely identifies each row?

A

super key

209
Q

a super key without unnecessary attributes?

A

candidate key

210
Q

each row in the table has its unique identity?

A

entity integrity

211
Q

no data entry?

A

nulls

212
Q

t or f: it is okay if there are nulls in other attributes?

A

false

213
Q

nulls can represent :

A

an unknown attribute value
a known but missing attribute value
a not applicable condition

214
Q

t or f: nulls can create logical problems when rational tables are linked?

A

true

215
Q

makes the relational database work. this is the def of?

A

controlled redundancy

216
Q

t or f: tables within the DB share common attributes?

A

true

217
Q

t or f: redundancy exists only when there is unnecessary duplication of attributes values?

A

true

218
Q

an attribute whose values match primary key values in the related table. this is the def of?

A

foreign key

219
Q

foreign key contains a value that refers to an existing valid tuple in another relation?

A

referential integrity

220
Q

key used strictly for data retrieval purposes?

A

secondary key

221
Q

t or f: many relational DB management enforce integrity rules automatically.

A

true

222
Q

why do designers use flags to avoid nulls?

A

flags indicate absence of some value

223
Q

provide a detailed accounting of all tables found within the user/designer created DB. this is the def of?

A

data dictionary

224
Q

t of f: data dictionary contain all attribute names characteristics for each table in the system and meta data?

A

true

225
Q

what does system catalogs contain:

A

metadata

detailed system data dictionary that describes all objects within the database

226
Q

indicates the use of the same name to label different attributes. this is the def of?

A

homonym

227
Q

opposite of homonym?

A

synonym

228
Q

the relational modeling idea?

A

1:m
and should be the norm in any relational DB design

229
Q

should be rare in any relational DB design?

A

1:1

230
Q

cant be implemented as such in the relational model?

A

m:n
can be changed to 1:M relationship

231
Q

one entity related to only one other entity

sometimes means that entity components were not defined properly

could indicate that two entities actually belong in the same table

certain conditions absolutely require their use

A

1:1

232
Q

implemented by breaking it up to produce a set of 1:M relationships

avoid problems inherent to M: N relationships by creating a composite entity; includes as foreign keys the primary keys of tables to be linked

A

the M:N relationships

233
Q

t or f: data redundancy leads to data anomalies that can destroy the effectiveness of the DB?

A

true

234
Q

control data redundancies by using common attributes shared by tables. this statement goes to the?

A

foreign key

235
Q

t or f: sometimes. data redundancy is unnecessary?

A

false

database (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions