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Systems Techniques and Documentation. Use of Systems Techniques in Systems Development. What are the three phases of a systems development project? Systems analysis Systems design Systems implementation. Systems Analysis. Systems analysis involves collecting and organizing facts.
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Use of Systems Techniques in Systems Development • What are the three phases of a systems development project? • Systems analysis • Systems design • 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 Disk Magnetic Tape
Specialized Input/Output Symbols Document Communication Link Manual Input Off-Line Storage Display
Specialized Process Symbols Auxiliary Operation Decision Predefined Process Merge Extract Preparation Collate Manual Operation Sort
Additional Symbols Connector Transmittal Tape Off-page Connector 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 Review and Approve Invoice Approved Invoice
Symbol Use in Flowcharting Reverse Flow Shown with Arrowheads Review and Approve Approved Invoice Invoice
Symbol Use in Flowcharting Use of Connector Symbol Purchasing Stores Requisition A Requisition A
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 Description: Calculate Gross Pay Author: Mr. Foxx Chart Number: 3.1 Date: 6/9/0X Input Process Output Accumulate hours worked Find correct pay rate Compute gross pay Payroll job record Payroll master file Gross pay records Payroll master file Error messages
Hierarchy Chart 1.0 Payroll System 2.0 3.0 4.0 Data Preparation Processing Review
Hierarchy Chart 3.1 3.2 Calculate Gross Pay Calculate Net Pay 3.11 3.12 3.13 Accumulate Hours Worked Compute Gross Pay Find Correct Pay Rate 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 FlowDiagram Symbols Terminator Process Data Flow Data Store
Data Flow Diagram Process Payroll Data Timekeeping Employees Payroll Data
Data Flow Diagram Employee Data Current Status Verify Payroll Data P1 Data Valid Payroll Data Timekeeping Valid Payroll Data
Data Flow Diagram Employee Data Net Pay and Deductions Calculate Pay P2 Data to Process Employees Paychecks Valid Payroll Data
Data Flow Diagram Update Employee Files Process Payroll Journal Journal Data Details Current Amounts Net Pay and Deductions Compute Net Pay Employees Paychecks
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 Suppliers Approve Vendor List Select Vendors Request for Quotation Prepare Quotation Request for Quotation
Analytic Flowchart Purchasing Suppliers Quotations Quotations Select Bid Prepare Purchase Order Purchase Order Purchase Order
Document Flowchart Controller Vice President Manufacturing Accounts Payable Purchasing Agent Receiving Stores Purchase Requisition 1 Purchase Requisition 1 Purchase Requisition 2 2 Purchase Order 3 To Vendor Purchase Order 1 2 Purchase Order 5 Purchase Order 4 3 4 5
Forms Distribution Chart Purchasing Inventory Payables Production Accounting Purchase Order Copy 1 1 1 2 2 2 3 3 4 4 5