Transcript Overview of Transaction Processing and Enterprise Resource

Systems Documentation
Techniques
Chapter 3
Copyright © 2015 Pearson Education, Inc.
3-1
INTRODUCTION
• Questions to be addressed in this chapter
include:
▫ What is the purpose of documentation?
▫ Why do accountants need to understand
documentation?
▫ What documentation techniques are used in
accounting systems?
▫ What are data flow diagrams and flowcharts?
 How are they alike and different?
 How are they prepared?
Copyright © 2015 Pearson Education, Inc.
INTRODUCTION
• How do accountants use documentation?
▫ At a minimum, they have to read documentation to
understand how a system works (e.g., auditors need to
assess risk).
▫ They may need to evaluate the strengths and
weaknesses of an entity’s 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
Copyright © 2015 Pearson Education, Inc.
Why Document Systems?
• Sarbanes-Oxley Act (SOX) requires management
to assess internal controls and auditors to
evaluate the assessment
• SAS-94 requires that auditors understand the
automated and manual procedures an entity
uses.
▫ This understanding can be gleaned through
documenting the internal control system—a
process that effectively exposes strengths and
weaknesses of the system.
• Used for systems development and changes
Copyright © 2015 Pearson Education, Inc.
3-4
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:
–
–
–
–
Copyright © 2015 Pearson Education, Inc.
Where data comes from
How it flows
The processes performed on it
Where it goes
INTRODUCTION
• In this chapter, we discuss two of the most
common documentation tools:
▫ Data flow diagrams
▫ Flowcharts
• Include three types:
– Document flowcharts describe the flow of documents and
information between departments or units.
– System flowcharts describe the relationship between inputs,
processing, and outputs for a system.
– Program flowcharts describe the sequence of logical
operations performed in a computer program.
Copyright © 2015 Pearson Education, Inc.
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
• An ERD is a data model, and a DFD is a process
model
Copyright © 2015 Pearson Education, Inc.
Data Flow Diagrams (DFD)
Focuses on the data flows for:
• Processes
• Sources and destinations of the data (also called
external entities)
• Data stores
DFD are visually simple, can be used to represent
the same process at a high abstract or detailed
level.
Copyright © 2015 Pearson Education, Inc.
3-8
DATA FLOW DIAGRAMS
• Data sources and destinations (External entities)
▫ Appear as squares
▫ Represent organizations, individuals, or organizational units that
send or receive data used or produced by the system
• An item can be both a source and a destination
• Used to define system boundaries
• Named with a noun
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
• Data sources and
destinations are marked
in red.
• Can you tell which are
sources and which are
destinations?
Customer
Customer
payment
1.0
Process
Payment
Accounts
Receivable
Remittance
data
Deposit
Bank
Copyright © 2015 Pearson Education, Inc.
2.0
Update
A/R
Receivables
Information
Credit
Manager
DATA FLOW DIAGRAMS
• Data flows
▫ Appear as arrows, named with nouns
▫ Represent the flow of data between sources and
destinations, processes, and data stores
▫ A data flow can be used to represent the creation,
reading, deletion, or updating of data in a file or
database (data store).
▫ At least one end of every data flow should either come
from or go to a process.
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
• Processes
▫ Appear as circles
▫ Represent the transformation of data
▫ Must be numbered and labeled with a single action
verb and an object
▫ Avoid the use of two verbs in the process name
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
•
•
The processes are shown in red.
Every process must have at least
one data inflow and at least one
data outflow.
Customer
Customer
payment
1.0
Process
Payment
Remittance
data
Deposit
Bank
Copyright © 2015 Pearson Education, Inc.
Accounts
Receivable
2.0
Update
A/R
Receivables
Information
Credit
Manager
DATA FLOW DIAGRAMS
• Data stores
▫
▫
▫
▫
▫
Appear as two horizontal lines, named with a noun
Represent a temporary or permanent data repository
Flow out of a data store = retrieval
Flow into a data store = inserting or updating
Data stores on a DFD are related to entities on an ERD
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
• Subdividing the DFD:
▫ Few systems can be fully diagrammed on one
sheet of paper, and users have needs for differing
levels of detail.
▫ Consequently, DFDs are subdivided into
successively lower levels to provide increasing
amounts of detail.
▫ Some data inputs and outputs will not appear on
the higher levels of the DFD but appear as the
processes are exploded into greater levels of detail.
Copyright © 2015 Pearson Education, Inc.
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
▫ The process symbol is numbered with a “0”
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
Govt.
Agencies
Departments
0
Payroll
Processing
System
Employee checks
Employees
Bank
Human
Resources
•
This is the context diagram for the
S&S payroll processing system
(Figure
Copyright © 2015 Pearson Education,
Inc. 3-5 in your textbook).
Management
DATA FLOW DIAGRAMS
• A Level 0 diagram is a projection of the process on the
Context diagram. It is like opening up that process and
looking inside to see how it works – to show the internal
sub-processes
• On a Level 0 diagram, you repeat the external entities
but you also expand the main process into its
subprocesses. Also data stores will appear at this level.
• The Level 0 diagram must “balance” with the Context
diagram. This means they should both have the same
external entities with the same flows to and from those
entities.
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
Departments
New employee
form
Human
Resources
This diagram
shows the
next level of
detail for the
context
diagram in
Figure 3-5.
Time
cards
1.0
Update
empl.
Payroll
file
Employee
Change
form
Employees
3.0
Prepare
reports
2.0
Pay
Employees
Employee/
Payroll file
Copyright © 2015 Pearson Education, Inc.
Payroll
check
Bank
5.0
Update
Gen.
Ledger
Payroll tax
disb. voucher
Payroll
report
Management
Payroll
Disbursement data
Employee
checks
4.0
Pay
taxes
General
Ledger
Tax report
& payment
Govt.
Agencies
DATA FLOW DIAGRAMS
Departments
Human
Resources
New employee
form
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.
Time
cards
1.0
Update
empl.
Payroll
file
Employee
Change
form
Employees
3.0
Prepare
reports
2.0
Pay
Employees
Employee/
Payroll file
Copyright © 2015 Pearson Education, Inc.
Payroll
check
Bank
5.0
Update
Gen.
Ledger
Payroll tax
disb. voucher
Payroll
report
Management
Payroll
Disbursement data
Employee
paychecks
4.0
Pay
taxes
General
Ledger
Tax report
& payment
Govt.
Agencies
DATA FLOW DIAGRAMS
• A Level 1 diagram is a projection of a Level 0
process.
• A Level 1 diagram shows all the processes that
comprise a single process on the level 0 diagram.
• It shows how information moves from and to
each of these processes.
• Level 1 diagrams may not be needed for all Level
0 processes.
• On Level 1 diagrams we do not repeat external
entities. Data stores may not be repeated either.
Copyright © 2015 Pearson Education, Inc.
CONTEXT DIAGRAM
KITCHEN
CUSTOMER
0
Customer Order
Receipt
Food
Ordering
System
Food Order
Management
Report
RESTAURANT
MANAGER
Copyright © 2015 Pearson Education, Inc.
LEVEL 0 DIAGRAM
KITCHEN
CUSTOMER
1.0
Customer Order
Transform
Customer
Food Order
Receipt
Food Order
3.0
2.0
Update
Goods Sold
Inventory
Data
Goods
Sold Data
Formatted
Inventory Data
Formatted Goods
Sold Data
D1
Update
Inventory
D2
GOODS SOLD
Daily Goods
Sold Amounts
Copyright © 2015 Pearson Education, Inc.
4.0
Produce
Management
Report
INVENTORY
Daily Inventory
Depletion Amounts
Management
Report
RESTAURANT
MANAGER
DFD Balance
KITCHEN
CUSTOMER
Customer Order
1.0
Receipt
Food Order
Transform
Customer
Food Order
3.0
2.0
Update
Inventory
Update
Goods Sold
Inventory
Data
Goods
Sold Data
Formatted Goods
Sold Data
D1
Formatted
Inventory Data
D2
GOODS SOLD
Daily Goods
Sold Amounts
Daily Inventory
Depletion Amounts
4.0
Produce
Management
Report
Management
Report
Copyright © 2015 Pearson Education, Inc.
RESTAURANT
MANAGER
INVENTORY
PROCESS 1 ON
THE LEVEL 0
DIAGRAM
SUB PROCESS 1
THIS LEVEL 1
DIAGRAM
Level 1 Diagram
1.1
Customer Order
Process
Customer
Order
Customer Order
1.3
Transform
Order to
Kitchen
Format
Food Order
1.5
Customer Order
Customer
Order
Inventory
Data
Generate
Inventory
Decrements
Customer Order
1.4
1.2
Generate
Customer
Receipt
Receipt
Copyright © 2015 Pearson Education, Inc.
Generate
Good Sold
Increments
Goods Sold Data
NOTE HOW WE HAVE THE SAME INPUTS
AND OUTPUTS AS THE ORIGINAL PROCESS
SHOWN IN THE LEVEL 0 DIAGRAM
Another Level 1 Diagram
ORGINAL
LEVEL 0
PROCESS
Daily Goods
Sold Amounts
4.0
Produce
Management
Report
Daily Inventory
Depletion Amounts
Management
Report
Daily Inventory
Depletion Amounts
Daily Goods
Sold Amounts
4.1
Access
Goods Sold
and Inventory
Data
Inventory Data
Goods Sold Data
LEVEL 1 PROCESSES
4.2
Aggregate
Goods Sold
and Inventory
Data
4.3
PROCESSES 2.0 AND 3.0 ON THE LEVEL 0 DIAGRAM
DO NOT NEED FURTHER DECOMPOSTION
Copyright © 2015 Pearson Education, Inc.
Prepare
Management
Report
Management
Report
Basic Guidelines for creating a DFD
• Understand the system that you
are trying to represent.
• A DFD is a simple
representation meaning that you
need to consider what is
relevant and what needs to be
included.
• Start with a high level (context
diagram) to show how data
flows between outside entities
and inside the system. Use
additional DFD’s at the detailed
level to show how data flows
within the system.
• Identify and group all the basic
elements of the DFD.
Copyright © 2015 Pearson Education, Inc.
• Name data elements with
descriptive names, use action
verbs for processes (e.g., update,
edit, prepare, validate, etc.).
• Give each process a sequential
number to help the reader
navigate from the abstract to the
detailed levels. A process labeled
5.0 would be exploded at the
next level into processes
numbered 5.1, 5.2, etc. A
process labeled 5.2 would be
exploded into 5.2.1, 5.2.2, etc
• Edit/Review/Refine your DFD
to make it easy to read and
understand.
3-27
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 employee’s payroll status occurs, such as a
raise or a change in the number of exemptions, 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.
Copyright © 2015 Pearson Education, Inc.
DATA FLOW DIAGRAMS
Departments
Human
Resources
New employee
form
Time
cards
1.0
Update
empl.
Payroll
file
Employee
Change
form
Employees
3.0
Prepare
reports
2.0
Pay
Employees
Employee/
Payroll file
Copyright © 2015 Pearson Education, Inc.
Payroll
check
Bank
5.0
Update
Gen.
Ledger
Payroll tax
disb. voucher
Payroll
report
Management
Payroll
Disbursement data
Employee
paychecks
4.0
Pay
taxes
General
Ledger
Tax report
& payment
Govt.
Agencies
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.
Copyright © 2015 Pearson Education, Inc.