Chapter 2 Systems Techniques and Documentation

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Chapter 2Systems Techniques and Documentation
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Presentation Outline
How does this system work?

1. Systems Techniques
2. Flowcharting Techniques
3. System Technique Symbols
4. The Use of Systems Techniques

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I. Systems Techniques

• Systems techniques are tools used in analysis,
  design, and documentation of system and subsystem
  relationships.
• Flowcharting
• Logical Data Flow Diagrams (DFDs)
• Charting Techniques
• Narrative Techniques
• Resource Utilization Analysis
• Decision Analysis Techniques

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A. Flowcharting
Read Record

• A flowchart is a symbolic diagram that shows the
  data flow and sequence of operations in a system.

Decision
Process 1
Process 2
Output
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B. Logical Data Flow Diagrams (DFDs)
A systems analyst often acts as the communication
link between users of a system and the
programmers/systems support staff who will
physically design the system to meet the user
needs.

• The intent of using DFDs is to separate clearly
  the logical process of systems analysis from the
  physical process of systems design. The systems
  analyst provides a logical description to the
  systems designer/programmer, who then designs the
  physical specification..

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C. Charting Techniques

• Hierarchy chart breaking down processing tasks
  into modules. See Figure 2-6 on page 38.
• IPO (Input-Process-Output) chart describing the
  input- process-output requirements of each
  module. See Figure 2-5 on page 38.

HIPO charts consist of two segments.
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D. Narrative Techniques

• Narrative techniques are often particularly
  useful in the fact finding stage of systems
  analysis. Various techniques include
• In depth and structured interviews
• Open-ended and closed-ended questionnaires
• Document reviews

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E. Resource Utilization Analysis

• Work measurement involves techniques used to
  identify tasks, obtain and adjust time estimates
  for the tasks, and analyze requirements in terms
  of total task time and capacity utilization
• Work distribution analysis involves assignment of
  tasks to employees. See Table 2-2 on page 50.

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F. Decision Analysis Techniques

• A decision symbol in a flowchart can only show
  two flow condition. More complex decision
  functions may be represented using one of the
  following
• Branching tables
• Decision tables

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1. Branching Tables

• A branching table consists of a single condition
  that can result in more than two paths of
  processing.

The Go to section contains either a connector
symbol reference or a single flowline to another
symbol.
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2. Decision Tables

• A decision table is similar to a branching table
  but more complex in that it incorporates multiple
  decision criteria.

Illustration
An analyst wishes to prepare a decision table
for purchase order procedures. First, there is a
credit check of the customer. If credit is
approved, the order is accepted. If the order
calls for 0 to 25 units, there is no discount on
the order. If the order calls for 26 to 55
units, it is eligible for a 5 percent discount
if more than 55 units are ordered, the discount
is 10 percent.
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An Example of a Limited-Entry Decision Table
Condition entries are limited to Y, N, or N/A
(-). Processing actions are either present or
absent.
Credit approved N Y Y Y
0 - 25 units - Y - -
26 - 55 units - - Y -
Over 55 units - - - Y

Reject order X
Accept order X X X
No discount X
5 discount X
10 discount X
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An Example of an Extended-Entry Decision Table
Entries indicate specific conditions, specific
actions to be taken, or reference to other
decision tables.
Credit approval N Y Y Y
Units in order - 0 25 26 55 Over 55

Order Acceptance N Y Y Y
Discount given 0 5 10
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II. Flowcharting Techniques

1. Systems Flowchart
2. Analytic Flowcharts
3. Document Flowcharts
4. Forms Distribution Chart
5. Program or Block Flowcharts

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A. Systems Flowcharts

• A systems flowchart is a graphical representation
  of the overall flow of work, documents, and
  operations in an application system. The
  sandwich rule states that every process should be
  sandwiched between an input symbol and and
  output symbol.

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B. Analytic Flowcharts

• Analytic flowcharts identify all significant
  processing in an application, emphasizing
  processing tasks that apply controls. In other
  words, functional areas are separated by columns.
  See Figure 2-10 on page 42.

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B. Document Flowcharts

• Identifies the point of origin, distribution, and
  ultimate disposition of each document used in an
  application system. See Figure 2-11 on page 43.

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C. Forms Distribution Chart

• Illustrates the distribution of a single multiple
  copy form within an organization. Emphasis is on
  form recipient rather than processing. (The
  following illustrates the Purchase Order in
  Figure 2-11 on page 43)

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E. Program or Block Flowcharts

• Program flowcharts are used by system developers
  to provide detail about individual processing
  functions. The clutter of the additional
  processing detail is thus removed from a
  flowchart showing overall processing.

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III. System Technique Symbols

1. Basic Flowcharting Symbols
2. Other Symbols

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A. Basic Flowcharting Symbols
Basic Input/Output Symbol Making data available
for processing or the recording of processed
information.
Process Transforming data into information or
other data.
Flowline Symbol Used to show the sequence of
information and processing.
Annotation Used to show descriptive comments.
- - - - -
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B. Other Symbols

• Specialized Input/Output Symbols See Figure 2-2
  on page 35.
• Data Flow Diagram Symbols See Symbols in Table
  2-1 on page 39. See Illustrations in Figures 2-7
  through 2-9 on pages 40-41.

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IV. The Use of Systems Techniques

1. Auditing
2. Systems Development

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A. Auditing

• Two basic components of an external audit of
  financial statements include
• Compliance testing is used to determine the
  extent to which established control procedures
  are actually being carried out.
• Substantive testing to verify amounts shown on
  financial statements. The level of substantive
  testing will depend on the extent to which the
  auditor depends on an entitys system of internal
  control.

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B. Systems Development
Systems development generally consists of the
following three phases

• Systems Analysis Logical data flow diagrams and
  analytic flowcharts help in providing an overall
  picture of the how the organization functions.
• Systems Design A blueprint of how the proposed
  system will function.
• Systems Implementation Taking steps to put
  system into operation by doing things like
  training personnel, and acquiring equipment and
  software.

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Summary

1. Five Types of Systems Techniques
2. Five Types of Flowcharting Techniques
3. Basic Flowcharting Symbols
4. Uses of Systems Techniques