DCIT24

Question 1

it is concerned with the nature and use of data

Answer 1

data analysis

Question 2

in practice, go directly from fact finding to implementation dependent data analysis

Answer 2

systems analysts

Question 3

establishing the nature of data

Answer 3

data analysis

Question 4

establishing the use of data

Answer 4

functional analysis

Question 5

the designer creates a written specification in words for the database system to be built

Answer 5

database study

Question 6

conceptual, logical, and physical design steps in taking specifications to physical implementable designs

Answer 6

database design

Question 7

it is quite possible that the database is to run on a machine which as yet does not have a database management system running on it

Answer 7

implementation and loading

Question 8

the database, once implemented, must be tested against the specification supplied by the client

Answer 8

testing and evaluation

Question 9

the system is actually in real usage by the company

Answer 9

operation

Question 10

designers rarely get everything perfect first time

Answer 10

maintenance and evolution

Question 11

often referred to as the three-level model

Answer 11

three-level database model

Question 12

the design moves from a written specification taken from the real-world requirements to a physically implementable design

Answer 12

three-level database model

Question 13

three levels of database model

Answer 13

• conceptual design
• data model mapping
• physical design

Question 14

takes the requirements and produces a high-level data model of the database structure

Answer 14

conceptual design phase

Question 15

the conceptual schema is converted into database internal structures

Answer 15

physical design phase

Question 16

process of creating a visual representation of either a whole
information system or parts of it to communicate connections between data points and structures

Answer 16

data modeling

Question 17

built around business needs

Answer 17

data models

Question 18

can be modeled at various levels of abstraction

Answer 18

data

Question 19

types of data models

Answer 19

• conceptual data models
• logical data models
• physical data models

Question 20

also referred to as domain models

Answer 20

conceptual data models

Question 21

offer a big-picture view of what the system will contain, how it will be organized, and which business rules are involved

Answer 21

conceptual data models

Question 22

less abstract and provide greater detail about the concepts and relationships in the domain

Answer 22

logical data models

Question 23

provide a schema for how the data will be physically stored within a database

Answer 23

physical data models

Question 24

they’re the least abstract of all

Answer 24

physical data models

Question 25

data modeling techniques

Answer 25

- hierarchical data modeling - network data modeling - relational data modeling - entity-relationship data modeling - dimensional data modeling - object-oriented data modeling - graph data modeling

Question 26

organize data in a treelike arrangement of parent and child records

Answer 26

hierarchical data modeling

Question 27

similar hierarchical method is also used today

Answer 27

XML or extensible markup language

Question 28

a popular data modeling option in mainframe databases that isn't used as much now

Answer 28

network data modeling

Question 29

allowing child records to be connected to multiple parent records

Answer 29

network data modeling

Question 30

a more flexible alternative to hierarchical and network ones

Answer 30

relational data modeling

Question 31

visually map entities, their attributes and the relationships between different entities

Answer 31

entity-relationship data modeling

Question 32

primarily used in data warehouses and data marts that support business intelligence applications

Answer 32

dimensional data modeling

Question 33

similar to the ER method, but it abstracts entities into objects

Answer 33

object-oriented data modeling

Question 34

a more modern offshoot of network and hierarchical models

Answer 34

graph data modeling

Question 35

steps of data modeling

Answer 35

- define an entity - define key properties for each entity - identify relationships between entities - mapping properties to entities - reduce redundance in performance requirements - complete and validate the data model

Question 36

benefits of data modeling

Answer 36

- internal agreement on data definitions and standards - increased involvement in data management by business users - more efficient database design at a lower cost - better use of available data assets

Question 37

the constraints, policies, and logic that govern how your data behaves and relates to each other

Answer 37

business rules

Question 38

business rules

Answer 38

- identify the sources - define the scope - express the rules - implement the rules

Question 39

a collection of tasks or processes that enhance the designing, development, implementation, and maintenance of enterprise data management system

Answer 39

database design

Question 40

it is not an important discussion that has to be taken forward in this article because we are focused on the database design

Answer 40

life cycle

Question 41

this stage is concerned with planning the entire DDLC (Database Development Life Cycle)

Answer 41

planning

Question 42

this stage covers the boundaries and scopes of the proper database after planning

Answer 42

system definition

Question 43

concerned with the practices and implementations of the logical model

Answer 43

physical model

Question 44

concerned with developing a model based on the proposed requirements

Answer 44

logical model

Question 45

used to import and convert data from the old to the new system

Answer 45

data conversion and loading

Question 46

concerned with error identification in the newly implemented system

Answer 46

testing

Question 47

a crucial step because it checks the database directly and compares the requirement specifications

Answer 47

testing

Question 48

process of determining the logical data structures that are required to support information resources within an organization

Answer 48

logical database design

Question 49

critical to the implementation of a corporate database

Answer 49

logical design

Question 50

represents the database as a collection of relations

Answer 50

relational model

Question 51

properties which define a relation

Answer 51

attributes

Question 52

stored along with its entities

Answer 52

table

Question 53

it represents records

Answer 53

rows

Question 54

it represents attributes

Answer 54

column

Question 55

a single row of a table, which contains a single record

Answer 55

tuple

Question 56

represents the name of the relation with its attributes

Answer 56

relation schema

Question 57

total number of attributes which in the relation

Answer 57

degree

Question 58

total number of rows present in the table

Answer 58

cardinality

Question 59

it represents the set of values for a specific attribute

Answer 59

column

Question 60

a finite set of tuples in the RDBMS system

Answer 60

relation instance

Question 61

every row has one, two or multiple attributes

Answer 61

relation key

Question 62

every attribute has some pre-defined value and scope

Answer 62

attribute domain

Question 63

conditions which must be present for a valid relation

Answer 63

relational integrity constraints

Question 64

can be violated if an attribute value is not appearing in the corresponding domain or it is not of the appropriate data type

Answer 64

domain constraints

Question 65

an attribute that can uniquely identify a tuple in a relation

Answer 65

key of the table

Question 66

based on the concept of Foreign Keys

Answer 66

referential integrity constraints

Question 67

an important attribute of a relation

Answer 67

foreign key

Question 68

a type of flowchart that illustrates how “entities” relate to each other within a system

Answer 68

entity relationship (ER) diagram

Question 69

a definable thing that can have data stored about it

Answer 69

entity

Question 70

group of definable things

Answer 70

entity type

Question 71

same as an entity type, but defined at a particular point in time

Answer 71

entity set

Question 72

an attribute that uniquely defines an entity in an entity set

Answer 72

entity keys

Question 73

set of attributes (one or more) that together define an entity in an entity set

Answer 73

super key

Question 74

minimal super key, it has the least possible number of attributes

Answer 74

candidate key

Question 75

a candidate key chosen by the database designer to uniquely identify the entity set

Answer 75

primary key

Question 76

how entities act upon each other or are associated with each other

Answer 76

relationship

Question 77

same entity participates more than once in the relationship

Answer 77

recursive relationship

Question 78

property or characteristic of an entity

Answer 78

attribute

Question 79

property or characteristic of a relationship

Answer 79

descriptive attribute

Question 80

the attribute value is atomic and can’t be further divided

Answer 80

simple

Question 81

sub-attributes spring from an attribute

Answer 81

composite

Question 82

attributed is calculated or otherwise derived from another attribute

Answer 82

derived

Question 83

more than one attribute value is denoted

Answer 83

multi-value

Question 84

just one attribute value

Answer 84

single value

Question 85

cardinality can be shown as look-across or same-side

Answer 85

cardinality views

Question 86

minimum or maximum numbers that apply to a relationship

Answer 86

cardinality constraints

Question 87

highest level in a data flow diagram // a tool popular among business analysts

Answer 87

context diagram

Question 88

first drawn in the middle of the chart // usually a circle shape that represents a conceptual boundary

Answer 88

context bubble

Question 89

represents all the external components that may interact with the system

Answer 89

system context diagram