DBAD

Question 0

A Data Dictionary stores:

Answer 0

Attribute name
Entity
Data Type
Size
Validation
Key

Question 1

A Data Dictionary is:

Answer 1

A catalogue of all data items in a system

Question 2

Types of validation are:

Answer 2

Presence check
Range check
Restricted choice check
Lookup

Question 3

Purpose of a data dictionary

Answer 3

Provides a detailed description of all data items that are in the system to ensure the validity and reliability of the data contained

Question 4

What is an entity event matrix?

Answer 4

A model to consider the entities in a system over a period of time

Question 5

Purpose of an Entity Event Matrix

Answer 5

Is used to record a list of all events that can occur and shows the effect they have on the entities within the system

Question 6

Purpose of an Entity Life History Diagram

Answer 6

Is used to record the sequence of events that can occur within any one entity.
It also indicates alternate and repeated events

Question 7

What is a Data Flow Diagram (DFD)?

Answer 7

Provides a graphical, non-technical representation of the system under consideration

Question 8

What is a Physical DFD?

Answer 8

Represents the system currently in use. It shows the actual way in which the system operates (Is implementation-dependant)

Question 9

What is a logical DFD?

Answer 9

It focuses on data flows between process without specifying physical characteristics (Implementation-independent)

Question 10

Purpose of a DFD

Answer 10

Provides a graphical representation of the components in the system. Shows input/output of data & movement of data between processes

Question 11

What does a DFD show?

Answer 11

Input/Output of data from/to entities that exist outside the system
Movement if data between processes & data stores that are inside the system

Question 12

Level 0 DFD (Context Diagram)

Answer 12

Shows a simple representation of the entire system.

It shows an overall Summary of the data flowing into and out of the system

Question 13

Level 1 DFD

Answer 13

Provides an overview of all major processes within the system

Question 14

Components of a DFD

Answer 14

Data flows
Physical flows
External entities
Data stores
Processes

Question 15

Conceptual design

Answer 15

A model of the information used within the business/organisation is constructed. Shows entities & relationships that will exist in new system. Independent of all physical considerations

Question 16

Logical design

Answer 16

See pp

Question 17

Physical design

Answer 17

Is produced after logical design. Provides a description of the database implementation in terms of storage devices, file organisation & security features

Question 18

Reasons why conceptual & logical design are separated from physical design

Answer 18

See pp

Question 19

System refinement

Answer 19

See pp

Question 20

Methods used to produce a Process Specification:

Answer 20

Standard English, Structured English, Graphical design notations

Question 21

Standard English

Answer 21

A few paragraphs of every day English would be used to describe a bottom level process

Question 22

Disadvantages of using Standard English

Answer 22

See pp

Question 23

Advantage of using Standard English

Answer 23

Natural language of both analyst, client & users therefore no additional learning.

Question 24

Structured English

Answer 24

Uses a restricted subset of the English language that can be easily coded and resembles a programming language. Clearly shows hierarchy of actions & events E.g. IF…ELSE…IF END, LOOP…LOOP END

Question 25

Graphical design notation: Structure charts…

Answer 25

Provide a means of breaking down a complex process and illustrating the components of the process diagrammatically

Question 26

A structure chart will show…

Answer 26

The sequence of events & activities, Any repetition (or iteration) of events, Any optional events

Question 27

What is a structure chart?

Answer 27

A hierarchical diagram that shows the relationships between the functions and actions that take place within a process

Question 28

Other graphical design notations/techniques

Answer 28

System flow charts, decision tables, decision trees, organisation charts

Question 29

Physical database design involves:

Answer 29

The selection of appropriate database management software, Deciding how to represent the logical model using the DBMS selected

Question 30

Importance of user interface design

Answer 30

More intuitive the user interface is, the easier it is to use. Better it is, easier to train people to use it, reducing training costs. Better it is, more users will like & want to use it, increasing client’s satisfaction

Question 31

Purpose of user interface:

Answer 31

Provide a front-end to the database system that allows users to interact with it without having to think about the underlying structures. Users want to find the information they need quickly with minimal amount of effort.

Question 32

User interface design includes:

Answer 32

Determining the type & interaction styles for user interface, Determining the layout of any screen forms, Planning the use that will be made of menus to allow users to interact with the system

Question 33

The design work (of user interface) should define:

Answer 33

How data entry screen should look, how menus will be organised into commands & sub menus, shortcut keys available, type of control used for data entry (text/list/check box), colour & navigation scheme etc.