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HAPTER 3

HAPTER 3. System Development and Documentation Techniques. 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?

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HAPTER 3

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  1. HAPTER 3 System Development and Documentation Techniques

  2. 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?

  3. 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 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

  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: • Where data comes from • How it flows • The processes performed on it • Where it goes

  5. 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.

  6. INTRODUCTION • Which method should you use—flowcharts or DFDs? • 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.

  7. 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

  8. DATA FLOW DIAGRAMS • A data flow diagram consists of four basic elements: • Data sources and destinations. Also called external entities • Data flows • Processes • Data stores

  9. 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

  10. Accounts Receivable Tue 12-10 (1) DATA FLOW DIAGRAMS • Data sources and destinations are marked in red. • Can you tell which are sources and which are destinations? 1.0 Process Payment 2.0 Update A/R Customer payment Customer Receivables Information Remittance data Credit Manager Deposit Bank

  11. 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.

  12. DATA FLOW DIAGRAMS • If two data elements flow together, then the use of one data flow line is appropriate. Process Payment Customer Cash Rec’t & Remittance Slip

  13. DATA FLOW DIAGRAMS • If the data elements do not always flow together, then multiple lines will be needed. Process Payment Customer Customer Inquiry Customer Payment

  14. 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 the word “and” in the process name

  15. Accounts Receivable DATA FLOW DIAGRAMS • The processes are shown in red. • Every process must have at least one data inflow and at least one data outflow. 1.0 Process Payment 2.0 Update A/R Customer payment Customer Receivables Information Remittance data Credit Manager Deposit Bank

  16. 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

  17. 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.

  18. Thu 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”

  19. DATA FLOW DIAGRAMS Govt. Agencies Depart- ments Tax report & payment Time cards Payroll Processing System Employees 0 Employee checks Payroll check New employee form Bank Employee change form Human Resources Payroll report • This is the context diagram for the S&S payroll processing system (Figure 3-5 in your textbook). Manage- ment

  20. Mon 11-10 (2) 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.

  21. Employee/ Payroll file General Ledger DATA FLOW DIAGRAMS Depart- ments Employees Employee checks Human Resources New employee form Time cards 1.0 Update empl. Payroll file 2.0 Pay Employ- ees Employee Change form Payroll check Bank Payroll Disburse- ment data 3.0 Prepare reports 5.0 Update Gen. Ledger This diagram shows the next level of detail for the context diagram in Figure 3-5. Payroll tax disb. voucher Payroll report 4.0 Pay taxes Manage- ment Tax report & payment Govt. Agencies

  22. Employee/ Payroll file General Ledger DATA FLOW DIAGRAMS Depart- ments Employees Employee paychecks Human Resources New employee form Time cards 1.0 Update empl. Payroll file 2.0 Pay Employ- ees Employee Change form Payroll check Bank 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. Payroll Disburse- ment data 3.0 Prepare reports 5.0 Update Gen. Ledger Payroll tax disb. voucher Payroll report 4.0 Pay taxes Manage- ment Tax report & payment Govt. Agencies

  23. 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.

  24. Extra HWCONTEXT DIAGRAM KITCHEN CUSTOMER 0 Customer Order Food Order Food Ordering System Receipt Management Report RESTAURANT MANAGER

  25. LEVEL 0 DIAGRAM KITCHEN CUSTOMER 1.0 Customer Order Food Order Transform Customer Food Order Receipt 3.0 2.0 Update Inventory Update Goods Sold Inventory Data Goods Sold Data Formatted Inventory Data Formatted Goods Sold Data INVENTORY D2 GOODS SOLD D1 Daily Inventory Depletion Amounts Daily Goods Sold Amounts 4.0 Produce Management Report RESTAURANT MANAGER Management Report

  26. DFD Balance KITCHEN CUSTOMER Customer Order 1.0 Food Order Receipt Transform Customer Food Order 3.0 2.0 Update Inventory Update Goods Sold Inventory Data Goods Sold Data Formatted Inventory Data Formatted Goods Sold Data INVENTORY D2 GOODS SOLD D1 Daily Inventory Depletion Amounts Daily Goods Sold Amounts 4.0 Produce Management Report Management Report RESTAURANT MANAGER

  27. Level 1 Diagram PROCESS 1 ON THE LEVEL 0 DIAGRAM SUB PROCESS 1 THIS LEVEL 1 DIAGRAM 1.3 1.1 Transform Order to Kitchen Format Process Customer Order Customer Order Food Order Customer Order Inventory Data 1.5 Customer Order Generate Inventory Decrements Customer Order Customer Order 1.4 1.2 Generate Good Sold Increments Generate Customer Receipt Goods Sold Data Receipt NOTE HOW WE HAVE THE SAME INPUTS AND OUTPUTS AS THE ORIGINAL PROCESS SHOWN IN THE LEVEL 0 DIAGRAM

  28. Another Level 1 Diagram Daily Goods Sold Amounts Daily Inventory Depletion Amounts 4.0 ORGINAL LEVEL 0 PROCESS Produce Management Report Management Report LEVEL 1 PROCESSES Daily Inventory Depletion Amounts 4.2 4.1 Inventory Data Daily Goods Sold Amounts Access Goods Sold and Inventory Data Aggregate Goods Sold and Inventory Data Goods Sold Data Management Report 4.3 Prepare Management Report PROCESSES 2.0 AND 3.0 ON THE LEVEL 0 DIAGRAM DO NOT NEED FURTHER DECOMPOSTION

  29. Mon 13-10 DATA FLOW DIAGRAMS • Let’s step through some guidelines on how to create a DFD. • RULE 1: Understand the system. Observe the flow of information and interview people involved to gain that understanding. • RULE 2: Ignore control processes and control actions (e.g., error corrections). Only very critical error paths should be included. • RULE 3: Determine the system boundaries—where it starts and stops. If you’re not sure about a process, include it for the time being.

  30. 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. • RULE 6: Data flows that always flow together should be grouped together. Those that do not flow together should be shown on separate lines. • RULE 7: Show a process (circle) wherever a data flow is converted from one form to another. Likewise, every process should have at least one incoming data flow and at least one outgoing data flow.

  31. DATA FLOW DIAGRAMS • RULE 8: Processes that are logically related or occur simultaneously can be grouped in one process. • RULE 9: Number each process sequentially. 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. • RULE 10: Process names should include action verbs, such as update, prepare, etc.

  32. DATA FLOW DIAGRAMS • RULE 11: Identify and label all data stores. • 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 avoid excessive or crossing lines. • RULE 13: As much as possible, organize the flow from top to bottom and left to right.

  33. DATA FLOW DIAGRAMS • RULE 14: You’re not likely to get it beautiful the first time, so plan to go through several iterations of refinements. • RULE 15: On the final copy, lines should not cross. On each page, include: • The name of the DFD • The date prepared • The preparer’s name

  34. 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.

  35. General Ledger DATA FLOW DIAGRAMS Depart- ments Employees Employee paychecks Human Resources New employee form Time cards 1.0 Update empl. Payroll file 2.0 Pay Employ- ees Employee Change form Payroll check Bank Payroll Disburse- ment data 3.0 Prepare reports 5.0 Update Gen. Ledger Employee/ Payroll file Payroll tax disb. voucher Payroll report 4.0 Pay taxes Manage- ment Tax report & payment Govt. Agencies

  36. 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.

  37. Mon 18-10 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 to depict processing procedures and the flow of data.

  38. FLOWCHARTS • Every shape on a flowchart depicts a unique operation, input, processing activity, or storage medium. • Before PC’s were common, flowcharts were commonly drawn 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.

  39. 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 origin to disposition and show: • Where a document comes from • Where it’s distributed • How it’s used • It’s ultimate disposition • Everything that happens as it flows through the system

  40. 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 inefficiencies such as: • Inadequate communication flows • Unnecessarily complex document flows • Procedures that cause wasteful delays • Document flowcharts are also prepared in the system Analysis process.

  41. Document Online keying (Manual input from keyboard) Display Input/output; Journal/ledger (Data) Flowcharting Symbols: Some Input Output Symbols Symbol Name

  42. Manual operations Computer processing Auxiliary operation (optical character scanner) Flowchart Symbols:Some Processing Symbols Symbol Name

  43. Magnetic disk (permanent) Magnetic tape Flowchart Symbols: Some Storage Symbols Symbol Name On-line Temporary Storage (General Data storage) (Stored data, moving data from one location to another)

  44. Document or processing flow On-page connector Off-page connector Terminal (Start, stop, begin, end) Decision Flowchart Symbols: Some Flow and Miscellaneous Symbols Symbol Name

  45. Document Flowchart Symbols A Multiple-part document Off-line File Document Terminal Journal/ Ledger Manual Process On-page Connector Off-page Connector Annotation

  46. This is part of the document flowchart from Figure 3-9 in your textbook.

  47. GUIDELINES FOR PREPARING A DOCUMENT FLOWCHART • Let’s step through some guidelines for preparing a document flowchart: • As with DFDs, you can’t effectively prepare a flowchart if you don’t understand the system, so: • Interview users, developers, auditors, and management. • Administer questionnaires. • Read through narratives. • Walk through systems transactions

  48. Tue 26-10 GUIDELINES FOR PREPARING A DOCUMENT FLOWCHART • Identify: • All departments using the system (the parties who “do” things in the story) • All documents or information flows • All processes performed on the documents • As you read through a narrative, you may want to mark the preceding items with different shapes (e.g., drawing a rectangle around entities, circling documents, etc.).

  49. GUIDELINES FOR PREPARING A DOCUMENT FLOWCHART • Use separate columns for the activity of each department. • Example: If there are three different departments or functions that “do” things in the narrative, there would be three columns on the flowchart. • Flowchart the normal course of operations, and identify exceptions with annotations. • As much as possible, the flow should go from top to bottom and left to right.

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