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C HAPTER 3

Systems Development and

Documentation Techniques

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INTRODUCTION

Questions to be addressed in this chapterinclude:

What is the purpose of documentation?

Why do accountants need to understanddocumentation?

What documentation techniques are used inaccounting systems?

What are data flow diagrams and flowcharts? How are they alike and different?

How are they prepared?

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INTRODUCTION

Documentation includes the following

types of tools:

Narratives (written descriptions)

Flowcharts

Diagrams

Other written material

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INTRODUCTION

Documentation covers the who, what,

when, where, why, and how of:

Data entry

Processing

Storage

Information output

System controls

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INTRODUCTION

How do accountants use documentation?

At a minimum, they have to read documentation to

understand how a system works.

They may need to evaluate the strengths andweaknesses of an entitys internal controls.

Requires heavy reliance on documentation.

They may peruse documentation to determine if a

proposed system meets the needs of its users. They may prepare documentation to:

Demonstrate how a proposed system would work

Demonstrate their understanding of a system of internal

controls

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INTRODUCTION

In this chapter, we discuss two of the most

common documentation tools:

Data flow diagrams

Graphical descriptions of the sources

and destinations of data. They show:

Where data comes from

How it flows

The processes performed on it Where it goes

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INTRODUCTION

In this chapter, we discuss two of the most

common documentation tools:

Data flow diagrams

Flowcharts Include three types:

Document flowchartsdescribe the flow of documents and

information between departments or units.

System flowchartsdescribe the relationship between inputs,processing, and outputs for a system.

Program flowchartsdescribe the sequence of logical

operations performed in a computer program.

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INTRODUCTION

Documentation techniques are necessarytoolsfor accountants: SAS-94requires that auditors understand the

automated and manual procedures an entity uses. This understanding can be gleaned through documenting the

internal control systema process that effectively exposesstrengths and weaknesses of the system.

SOX (2002)effectively requires that publicly-tradedcorporations and their auditors document and test thecompanys internal controls.

Auditing Standard No. 2promulgated by thePCAOB requires that the external auditor express anopinion on the clients system of internal controls.

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INTRODUCTION

Documentation tools help accountants by:

Organizing very complicated systems into a

form that can be more readily understood

Helping new team members understand a

pre-existing system

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INTRODUCTION

Which method should you useflowcharts

or DVDs?

62.5% of IS professionals use DFDs.

97.6% use flowcharts.

Both can be prepared relatively simply using

available software.

Both are tested on professional exams.

CONCLUSION: You need to know them both.

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DATA FLOW DIAGRAMS

A data flow diagram (DFD) graphically

describes the flow of data within an

organization. It is used to:

Document existing systems

Plan and design new systems

There is no black-and-white approach to

developing a DFD.

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

Example of a data flow

diagram of the customer

payment process from

Figure 3-3 in your

textbook

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DATA FLOW DIAGRAMS

A data flow diagram consists of four basic

elements:

Data sources and destinations

Data flows

Transformation processes

Data stores

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DATA FLOW DIAGRAMS


elements:


Data flows


Data stores

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DATA FLOW DIAGRAMS


Appear as squares

Represent organizations or individuals that send or

receive data used or produced by the system An item can be both a source and a destination

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

Data sources and

destinations are marked

in red.

Can you tell which are

sources and which are

destinations?

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DATA FLOW DIAGRAMS


elements:


Data flows


Data stores

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DATA FLOW DIAGRAMS

Data flows

Appear as arrows

Represent the flow of data between sources and

destinations, processes, and data stores

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

Data flows are shown in red.

Does it appear that a data

flow can be two-way?

If so, how is it handled?

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

Data flows should always belabeled.

The exception is a data flow

moving into or out of a data

store.

What symbol is the data store?

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DATA FLOW DIAGRAMS

As you probably surmised from the previous

slides, if a data flow is two-way, use a bi-

directional arrow.

Update

Receiv-

ables

General

Ledger

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DATA FLOW DIAGRAMS

If two data elements flow together, then the use

of one data flow line is appropriate.

CustomerProcess

Payment

Cash Rect & Remittance Slip

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DATA FLOW DIAGRAMS

If the data elements do not always flow

together, then multiple lines will be

needed.

Customer ProcessPayment

Customer Inquiry

Customer Payment

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DATA FLOW DIAGRAMS


elements:


Data flows


Data stores

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DATA FLOW DIAGRAMS

Processes

Appear as circles

Represent the transformation of data

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

The transformation processes areshown in red.

Every process must have at least

one data inflow and at least one

data outflow. Why?

What do you notice about how theprocesses are labeled?

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DATA FLOW DIAGRAMS

Data stores

Appear as two horizontal lines

Represent a temporary or permanent repository of

data

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DATA FLOW DIAGRAMS

Customer1.0

Process

Payment

2.0

Update

A/R

Credit

Manager

Bank

Accounts

Receivable

Customer

paymentRemittance

data

Receivables

Information

Deposit

The data store is shown in red.

Notice that the inflows and

outflows to the data store are

not labeled.

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DATA FLOW DIAGRAMS

Data dictionary:

Data flows and data stores are typically

collections of data elements.

EXAMPLE: A data flow labeled student

in format ionmight contain elements such as

student name, date of birth, ID number,

address, phone number, and major.

The data dictionarycontains a description of

all data elements, data stores, and data flows

in a system.

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DATA FLOW DIAGRAMS

The highest level of DFD is called a

context diagram.

It provides a summary-level view of the

system.

It depicts a data processing system and the

external entities that are:

Sources of its input Destinations of its output

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DATA FLOW DIAGRAMS

PayrollProcessing

System

Depart-

ments

HumanResources

Govt.

Agencies

Employees

Bank

Manage-

ment

Employee checks

This is the context diagram for the

S&S payroll processing system

(Figure 3-5 in your textbook).

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DATA FLOW DIAGRAMS

PayrollProcessing

System

Depart-

ments

HumanResources

Govt.

Agencies

Employees

Bank

Manage-

ment

Employee checks

What information is produced by this

process, and where does it go?

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data

Payroll taxdisb. voucher

Tax report

& payment

Payroll

report

This diagram

shows the

next level ofdetail for the

context

diagram in

Figure 3-5.

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

What

information

comes intothese

processes

and from

where?

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

What

information is

produced bythese

processes,

and where

does it go?

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

How do the

sources and

destinationsdiffer from

the context

diagram?

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DATA FLOW DIAGRAMS

1.0Update

empl.

Payrollfile

2.0Pay

Employ-ees

5.0Update

Gen.

Ledger

4.0Pay

taxes

3.0Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

Notice that

each process

in the DFD isnumbered

sequentially.

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Changeform

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

Suppose we

exploded Process

2.0 (pay

employees) in the

next level. The

sub-processes

would be

numbered 2.1, 2.2,

2.3, etc.

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DATA FLOW DIAGRAMS

Were going to go into a partial example of

how the first level of detail was created.

But before we do, lets step through some

guidelines on how to create a DFD.

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DATA FLOW DIAGRAMS

RULE 1: Understand the system. Observe the

flow of information and interview people involved

to gain that understanding.

RULE 2: Ignore control processes and controlactions (e.g., error corrections). Only very

critical error paths should be included.

RULE 3: Determine the system boundaries

where it starts and stops. If youre not sure

about a process, include it for the time being.

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DATA FLOW DIAGRAMS

RULE 4: Draw the context diagram first, and

then draw successively greater levels of detail.

RULE 5: Identify and label all data flows. The

only ones that do not have to be labeled arethose that go into or come out of data stores.

RULE 6: Data flows that always flow together

should be grouped together. Those that do not

flow together should be shown on separate

lines.

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DATA FLOW DIAGRAMS

RULE 10: Process names should include action

verbs, such as update, prepare, etc.

RULE 11: Identify and label all data stores,

whether temporary or permanent. RULE 12: Identify and label all sources and

destinations. An entity can be both a source and

destination. You may wish to include such items

twice on the diagram, if needed, to avoidexcessive or crossing lines.

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DATA FLOW DIAGRAMS

The first paragraph of the narrative for the payroll

process reads as follows:

When employees are hired, they complete a new employee

form. When a change to an employees payroll status occurs,

such as a raise or a change in the number of exemptions, humanresources completes an employee change form. A copy of these

forms is sent to payroll. These forms are used to create or

update the records in the employee/payroll file and are then

stored in the file. Employee records are stored alphabetically.

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DATA FLOW DIAGRAMS




form. When a change to an employees payroll status

occurs, such as a raise or a change in the number ofexemptions, human resources completes an employee

change form. A copy of these forms is sent to payroll.

These forms are used to create or update the records in the

employee/payroll file and are then stored in the file.

Employee records are stored alphabetically.

The portion marked in red relates to activities that go on

outside the boundaries of the payroll system. Consequently,

these activities will not be included on the DFD.

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DATA FLOW DIAGRAMS










The portion marked in red suggests two data flows coming into

the payroll process (new employee forms and employee

change forms). The source of the inflows is the human

resources department.

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DATA FLOW DIAGRAMS

Data Inputs Processes Data Outputs

New employee forms and

employee change forms

(from H.R. Dept.)

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DATA FLOW DIAGRAMS










The sentence marked in red suggests a process (update

employee records) with the data outflow going to a data store

(the employee/payroll file).

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DATA FLOW DIAGRAMS




(from H.R. Dept.)

Update records (read from

file and record)

Updated employee/

payroll file

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DATA FLOW DIAGRAMS










The final sentence in this paragraph provides information

about the physical storage of the data. Physical information is

utilized in flowcharts but not in data flow diagrams.

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DATA FLOW DIAGRAMS




(from H.R. Dept.)

Update records (read from

file and record)

Updated employee/

payroll file

We will not do the entire DFD, however, you could finish thistable by reading the remainder of the narrative in Table 3-1 in

your textbook. The portion of the table completed so far allows

us to draw the segment of the DFD that is highlighted on the

following slide.

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DATA FLOW DIAGRAMS

1.0

Update

empl.

Payrollfile

2.0

Pay

Employ-ees

5.0

Update

Gen.

Ledger

4.0

Pay

taxes

3.0

Prepare

reports

Employee/

Payroll file

General

Ledger

Human

Resources

Depart-

ments Employees

Bank

Govt.

Agencies

Manage-

ment

Employee

Change

form

New employee

form

Time

cards

Employee

paychecks

Payroll

check

Payroll

Disburse-

ment data


Tax report

& payment

Payroll

report

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DATA FLOW DIAGRAMS

Keep the following in mind as you develop your

DFD:

Remember to ignore control activities, such as error

correction processes.

Some data inputs and outputs will not appear on the

first level of the DFD but appear as the processes are

exploded into greater levels of detail.

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DATA FLOW DIAGRAMS

The data flow diagram focuses on the logical

flow of data.

Next, we will discuss flowcharts, which place

greater emphasis on physical details.

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FLOWCHARTS

A flowchart is an analytical technique that

describes some aspect of an information system

in a clear, concise, and logical manner.

Flowcharts use a set of standard symbols todepict processing procedures and the flow of

data.

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FLOWCHARTS

Every shape on a flowchart depicts a unique

operation, input, processing activity, or storage

medium.

In the days of yore, flowcharts were commonlydrawn with templates.

Now, it is more common to use a software

program such as Visio.

Microsoft and Power Point are also used

The software uses pre-drawn shapes, and the

developer drags the shapes into the drawing.

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FLOWCHARTS

There are four types of flowcharting

symbols:

Input/output symbols

Processing symbols

Processing symbols indicate the type

of device used to process the data or

whether the data is processed

manually.

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FLOWCHARTS


symbols:


Processing symbols

Storage symbolsStorage symbols indicate the type of

device used to store data while the

system is not using it.

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FLOWCHARTS


symbols:


Processing symbols

Storage symbols

Flow and miscellaneous symbols

Flow and miscellaneous symbols may

indicate:

The flow of data and goods

The beginning or end of the flowchart

The location of a decision

An explanatory note

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FLOWCHARTS

Click on buttons below if you wish to

review symbols in the various categories.

Input/Output

Symbols

Processing

Symbols

Storage

Symbols

Flow & Misc.

Symbols

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DOCUMENT FLOWCHARTS

A document flowchart shows the flow of

documents and information among areas of

responsibility in an organization.

These flowcharts trace a document from cradleto grave and show:

Where a document comes from

Where its distributed

How its used

Its ultimate disposition

Everything that happens as it flows through the

system

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DOCUMENT FLOWCHARTS

Internal control flowcharts are document

flowcharts used to evaluate the adequacy of

internal controls, such as segregation of duties or

internal checks.

They can reveal weaknesses or inefficiences such

as:

Inadequate communication flows

Unnecessarily complex document flows Procedures that cause wasteful delays

Document flowcharts are also prepared in the

system design process.

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This is part of the

document flowchart

from Figure 3-9 in

your textbook.

GUIDELINES FOR PREPARING

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FLOWCHARTS

Lets step through some guidelines for

preparing flowcharts:

As with DFDs, you cant effectively prepare a

flowchart if you dont understand the system,so:

Interview users, developers, auditors, and

management.

Administer questionnaires.

Read through narratives.

Walk through systems transactions

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FLOWCHARTS

Use separate columns for the activity of

each entity.

Example: If there are three different

departments or functions that do things inthe narrative, there would be three columns

on the flowchart.

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What are the entities

in this flowchart?

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FLOWCHARTS

Give the flowchart a clear beginning andending. Show where each document originated and its final

disposition.

One approach you can use is to read throughthe narrative and for each step define: What was (were) the input(s)

What process was carried out

What was (were) the output(s)

Note on the next slide that the flow sequenceis input -- processoutput.

Identifies where input is coming from

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Inputs

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Input for

next

process

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Process

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Filing

a document

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FLOWCHARTS

When using multiple copies of adocument, place document numbers in

the upper, right-hand corner.

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SYSTEM FLOWCHARTS

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SYSTEM FLOWCHARTS

Now that weve looked at documentflowcharts and guidelines for creating

flowcharts, lets take a brief look at system

flowcharts.

SYSTEM FLOWCHARTS

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SYSTEM FLOWCHARTS

A system flowchart depicts the relationshipamong the inputs, processes, and outputs

of an AIS.

The system flowchart begins by identifyingthe inputs to the system.

These inputs can be:

New data

Data stored for future use

Both

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The program flowchart from

Figure 3-11 in your textbook

is shown on the right.

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Note that the program flowchart

details the logic of processes

performed by the computer.

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FLOWCHARTS VS DFDs

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FLOWCHARTS VS. DFDs

Now that weve examined both flowchartsand DFDs, it may be useful to discuss the

differences again.

DFDs place a heavy emphasis on thelogical aspects of a system.

Flowcharts place more emphasis on the

physical characteristics of the system. An example may be useful.

FLOWCHARTS VS DFDs

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FLOWCHARTS VS. DFDs

EXAMPLE: The registrars office of asmall college receives paper enrollmentforms from students. They sort theserecords alphabetically and then update thestudent record file to show the newclasses. They also prepare class lists fromthe same data. The sorted enrollment

forms are forwarded to the bursars officefor billing purposes. Class lists are mailedto faculty members.

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Students Students

Registrars Office

Enrollment Sort

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Students

1.0

Update

Student

Records

2.0

Prepare

Class Lists

Student

Records

Faculty

Bursar

Enrollment

Forms

EnrollmentForms

Enrollment

Forms

Class

Lists

StudentsForms

Sort

Forms

Sorted

Enrollment

Forms

Update

Student

Records

A

Prepare

Class

Lists

SortedEnrollment

Forms

Class

Lists

Sorted

EnrollmentForms

BursarFaculty

Heres a

flowchart

that goeswith the

story

FLOWCHARTS VS DFDs

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FLOWCHARTS VS. DFDs

Now lets change the story so thatstudents enter enrollment data online.

The registrars office sends a tape file of

the enrollment data to the bursars officeand continues to send paper class lists to

faculty.

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FLOWCHARTS VS. DFDs

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FLOWCHARTS VS. DFDs

Moral of the Story: Changes in thephysical characteristics of the process do

affect the flowchart but have little or no

impact on the DFD. The DFD focuses more on the logic.

When deciding which tool to employ,

consider the information needs of thosewho will view it.

QUIZ QUESTION

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QUIZ QUESTION

How is playing the piano like making DFDsand flowcharts?

You cant learn to do it by just watching

someone else. You cant learn to do it by just looking at

examples.

Your first attempts are clumsy.

Practice leads to improvement and maybe

even perfection.

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Date post:	02-Jun-2018
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