Transcript Systems Techniques and Documentation

Systems Techniques
and Documentation
Use of Systems Techniques in Systems
Development
• What are the three phases of a systems
development project?
1 Systems analysis
2 Systems design
3 Systems implementation
Systems Analysis
• Systems analysis involves collecting and organizing
facts.
• Systems techniques assist the analyst in performing
these tasks.
• What are some of these techniques?
– matrix techniques
– logical data flow diagrams
Systems Implementation
• Systems implementation involves the actual carrying
out of the design plan.
• Documentation is one of the most important parts of
systems implementation.
• What systems techniques serve as a documentation
tool?
– program flowcharts
– decision tables
Systems Techniques
• What is a flowchart?
• A flowchart is a symbolic diagram that shows the data
flow and sequence of operations in a system.
• Flowcharts are probably the most common systems
technique.
Basic Symbols
Input/Output
Process
Flowline
Annotation
Specialized Input/Output Symbols
Punched Card
Punched Tape
On-Line Storage
Magnetic Tape
Magnetic Disk
Specialized Input/Output Symbols
Document
Communication
Link
Manual Input
Display
Off-Line Storage
Specialized Process Symbols
Decision
Auxiliary
Operation
Predefined
Process
Merge
Preparation
Extract
Manual
Operation
Collate
Sort
Additional Symbols
Connector
Off-page Connector
Transmittal Tape
Terminal
Parallel Mode
Symbol Use in Flowcharting
• Symbols are used in a flowchart to represent the
functions of an information or other type of system.
• Normal direction of flow is from left to right and top to
bottom.
• Open arrowheads should be used on reverse-direction
flowlines
Symbol Use in Flowcharting
Normal Direction of Flow
Invoice
Review
and
Approve
Approved
Invoice
Symbol Use in Flowcharting
Reverse Flow Shown with Arrowheads
Approved
Invoice
Review
and
Approve
Invoice
Symbol Use in Flowcharting
Use of Connector Symbol
Stores
Purchasing
Requisition
A
A
Requisition
Symbol Use in Flowcharting
Bidirectional Flow Shown with Arrowheads
Requisition
Prepare Purchase
Order and Update
Vendor Files
Vendor
Files
Purchase
Order
Learning Objective
Define common systems techniques, such as
HIPO charts, systems flowcharts, and logical
data flow diagrams.
IPO and HIPO Charts
• These charts are used primarily by systems
development personnel.
• At the most general level of analysis only the basic
input-process-output relations in a system are of
concern.
• Additional processing detail is provided by
hierarchy plus input-process-output.
IPO Chart
System: Payroll
Author: Mr. Foxx
Chart Number: 3.1
Input
Description: Calculate
Gross Pay
Payroll job record
Accumulate hours worked Gross pay records
Find correct pay rate
Payroll master file
Payroll master file
Process
Compute gross pay
Date: 6/9/0X
Output
Error messages
Hierarchy Chart
1.0
Payroll System
2.0
3.0
Data Preparation
4.0
Processing
Review
Hierarchy Chart
3.1
3.2
Calculate Gross
Pay
3.11
Calculate Net Pay
3.12
Accumulate Hours
Worked
Find Correct Pay
Rate
3.13
Compute Gross
Pay
Each numbered module would be detailed in an IPO chart.
Systems and Program Flowcharts
• A systems flowchart identifies the overall or broad
flow of operations in a system.
• The focus of systems flowcharting concerns media
and processing functions rather than the detailed
logic of individual processing functions.
Logical Data Flow
Diagram Symbols
Terminator
Process
Data Store
Data Flow
Data Flow Diagram
Timekeeping
Process
Payroll
Data
Payroll Data
Employees
Data Flow Diagram
Current Status
Timekeeping
Payroll
Data
Verify
Payroll
Data
P1
Employee Data
Data Valid
Valid Payroll Data
Data Flow Diagram
Employee Data
Data to Process
Net Pay and
Deductions
Calculate
Pay
P2
Valid Payroll Data
Paychecks
Employees
Data Flow Diagram
Update
Employee
Files
Net Pay and
Deductions
Compute
Net Pay
Current
Amounts
Process
Payroll
Journal
Details
Paychecks
Journal
Data
Employees
Analytic, Document, and Forms
Distribution Flowcharts
• An analytic flowchart identifies all significant processing
in an application, emphasizing processing tasks that
apply controls.
• In an analytic flowchart the flow of processing is
depicted using symbols connected with flowlines.
Analytic, Document, and Forms
Distribution Flowcharts
• A document flowchart is similar in format to an analytic
flowchart but contains less detail about the processing
functions of each entity shown on the chart.
• The only symbol used in a document flowchart is the
document symbol.
Analytic, Document, and Forms Distribution
Flowcharts
• The forms distribution chart illustrates the
distribution of multiple copy forms with an
organization.
• The emphasis is on who gets what forms rather
than on how these forms are processed.
Analytic Flowchart
Purchasing
Approve
Vendor
List
Suppliers
Select
Vendors
Prepare
Quotation
Request
for
Quotation
Request
for
Quotation
Analytic Flowchart
Purchasing
Suppliers
Quotations
Select
Bid
Quotations
Prepare
Purchase
Order
Purchase
Order
Purchase
Order
Document Flowchart
Controller
Vice President Manufacturing
Accounts Payable Purchasing Agent Receiving Stores
Purchase
Purchase
Requisition
Requisition
1
2
Purchase
Purchase
Order
To Vendor
Order
3
1 2
Purchase
34
Order
5
5
Purchase
Requisition
1
2
Purchase
Order
4
Forms Distribution Chart
Purchasing Inventory Payables Production Accounting
Purchase
Order Copy
1
2
1
1
2
2
3
4
5
3
4