Systems Development and Documentation Techniques

1. Systems Development and Documentation Techniques 6 UAA – ACCT 316 – Fall 2003 Accounting Information Systems Dr. Fred Barbee Chapter

2. Documentation Techniques Used by 62.5% of IT Professionals • Data Flow Diagrams • Document Flowcharts • System Flowcharts • Program Flowcharts Used by 97.6% of IT Professionals

3. Documentation Techniques • Data Flow Diagrams • Document Flowcharts • System Flowcharts • Program Flowcharts More than 92% use both DFDs and flowcharts.

4. Typical Information System • Computer-based; • Has a number of terminals connected to it via telecommunications links; • Is used by dozens of people within and outside the organization;

5. Typical Information System • Has hundreds of programs that perform functions for virtually every department in the organization. • Processes thousands of transactions and hundreds of requests for management information.

6. to “see” and analyze all the inputs and outputs. For such a system . . . We need “pictures” rather than a narrative description

7. Using Document Flowcharts Who? Where? What?

8. Documentation Techniques • . . . are tools used in analyzing, designing, and documenting system and subsystem relationships . . .

9. Documentation Techniques • They are largely graphical in nature; • Are essential to both internal and external auditors; and • Are indispensable in the development of information systems.

10. Auditors

11. Systems Development

12. Management

13. Other Users

14. You! Prepare Evaluate Read

15. Classification . . . • Documentation is classified according to the level of the accounting system to which it relates.

16. Typical System Documentation • System narrative descriptions • Block diagrams • Document flowcharts • Data flow diagrams

17. Overall System Documentation • System Flowcharts • Program Flowcharts; and • Decision Flowcharts

18. In Terms of Level of Detail Narrative descriptions are the most general overview and correspondingly show the fewest details. • Systemflowchartsprovide less of an overview, but include the mostdetail in this class of documentation.

19. Narrative Descriptions • A written step-by-step explanation of system components and interactions. • The highest and broadest form of documentation at the overall system level.

20. Block Diagrams • Block diagrams provide a graphic overview of a system. • Commonly used to provide an overview of an accounting system in terms of its major components and subsystems

21. Block Diagrams • They help people understand a system without getting bogged down in details. • Two types: • Horizontal Block Diagram; and • Hierarchical Block Diagram

22. Purchasing Cycle Request for Goods and Services Purchase Requisition Purchasing Purchase Order Receiving Report Receiving Document Process $ Cash Disb. Voucher Disb. Approval

23. Vendors and Employees Customer Customer Customer Horizontal Block Diagram Bank

24. Hierarchical Block Diagrams • Show the analysis of a system into successive levels of component subsystems. • Connecting lines represent interlevel associations (parent-child relationships).

25. Hierarchical Block Diagram of The Revenue Cycle

26. Bridge the gap between Broad documentation types . . . System Narratives Block Diagrams Document Flow charts Data Flow Diagrams • Narrow documentation types . . . • System Flow Charts

27. Data Flow Diagrams • Provide . . . • More detailed representation of an accounting system than block diagrams • Fewer technical details than system flowcharts.

28. Symbols For Data Flow Diagrams Figure 6-1 (p. 158)

31. Data Flow Diagrams • The DFD should consist solely of DFD symbols; • Each symbol in the DFD, including each pointed flowline, should be labeled;

32. Data Flow Diagrams • All names must be meaningful to the end-user. • All symbols must have an individual name. • Diagrams are always named at the top or bottom. • The name should identify the level and the system it represents.

33. Figure 6-2 Basic Data Flow Diagram Elements

34. AKA “Entity,” or “terminator.” Named with descriptive nouns or noun clauses. AKA “Entity,” or “terminator.” Named with descriptive nouns or noun clauses. Figure 6-2 Basic Data Flow Diagram Elements Examples: Customer, Employees, Bank, etc.

35. Named with action verb or verb clause. The name must describe what action or transformation is occurring. Figure 6-2 Basic Data Flow Diagram Elements Examples: Process Payment, Update Receivables, etc.

36. Examples: Accounts Receivable, General Ledger, etc. Figure 6-2 Basic Data Flow Diagram Elements Named with a noun clause that describes the contents of the data store. Should not include the word “data.”

37. AKA “Entity,” or “terminator.” Named with descriptive nouns or noun clauses. Named with a noun clause that describes the data carrier and how it is implemented. Figure 6-2 Basic Data Flow Diagram Elements Examples: Time Cards; Employee Data, etc.

38. Figure 6-3 Data Flow Diagram of Customer Payment process

39. DFDs – Some Do’s and Don’ts First – the Do’s

40. All data flows must begin at a process, end at a process, or both. DFDs – Some Do’s and Don’ts

41. Data stores cannot communicate with entities DFDs – Some Do’s and Don’ts

42. Entities cannot communicate with other entities. DFDs – Some Do’s and Don’ts

43. Data stores cannot communicate with other data stores. DFDs – Some Do’s and Don’ts

44. Processes can communicate with other processes. DFDs – Some Do’s and Don’ts

45. All processes must have an incoming and outgoing data flow. DFDs – Some Do’s and Don’ts

46. All entities must be introduced at the context level. DFDs – Some Do’s and Don’ts

47. Only entities and data store symbols may be duplicated. DFDs – Some Do’s and Don’ts

48. Do not cross data flows. DFDs – Some Do’s and Don’ts

49. Do not use double-ended arrow to represent data flows. DFDs – Some Do’s and Don’ts

50. Do not use diverging arrow to represent data flows DFDs – Some Do’s and Don’ts OK