Chapter 3: Systems Documentation Techniques

Chapter 3Systems Documentation TechniquesCopyright © 2012 Pearson Education3-1Learning ObjectivesPrepare and use data flow diagrams to understand, evaluate, and document information systems.Prepare and use flowcharts to understand, evaluate, and document information systems.Copyright © 2012 Pearson Education3-2What Is Documentation?Set of documents and modelsNarratives, data flow models, flowchartsDescribe who, what, why, when, and where of systems:Input, process, storage, output, and controlsCopyright © 2012 Pearson Education3-3Why Should You Learn Documentation?You need to be able to read documentation in all its forms: narratives, diagrams, models.You need to be able to evaluate the quality of systems, such as internal control based in part on documentation.SAS 94 requires independent auditors to understand all internal control procedures.Documentation assists in auditor understanding and documentation of their understandingSarbanes-Oxley states that management:Is responsible for internal control systemIs responsible for assessing the effectiveness of the IC SystemBoth management and external auditors need to document and test IC SystemCopyright © 2012 Pearson Education3-4Data Flow DiagramsGraphically describes the flow of data within a systemFour basic elementsCopyright © 2012 Pearson Education3-5EntityProcessData FlowData StoreEntityRepresents a source of data or input into the system orRepresents a destination of data or output from the systemCopyright © 2012 Pearson Education3-6Data FlowsMovement of data among:Entities (sources or destinations)ProcessesData storesLabel should describe the information movingCopyright © 2012 Pearson Education3-7ProcessRepresents the transformation of dataCopyright © 2012 Pearson Education3-8Data StoreRepresents data at restCopyright © 2012 Pearson Education3-9Data Flow Diagram LevelsContextHighest level (most general)Purpose: show inputs and outputs into systemCharacteristics: one process symbol only, no data storesLevel-0Purpose: show all major activity steps of a systemCharacteristics: processes are labeled 1.0, 2.0, and so onCopyright © 2012 Pearson Education3-10DFD Creation GuidelinesUnderstand the systemIgnore certain aspects of the systemDetermine system boundariesDevelop a context DFDIdentify data flowsGroup data flowsNumber each processIdentify transformational processesGroup transformational processesIdentify all data storesIdentify all sources and destinationsLabel all DFD elementsSubdivide DFDCopyright © 2012 Pearson Education3-11FlowchartsUse symbols to logically depict transaction processing and the flow of data through a system.Using a pictorial representation is easier to understand and explain versus a detailed narrative.Copyright © 2012 Pearson Education3-12Flowchart Symbol CategoriesInput/OutputProcessingStorageMiscellaneousCopyright © 2012 Pearson Education3-13Flow Chart Symbol Categories(cont’d)Copyright © 2012 Pearson EducationTypes of FlowchartsDocumentIllustrates the flow of documents through an organizationUseful for analyzing internal control proceduresSystemLogical representation of system inputs, processes, and outputsUseful in systems analysis and designProgramRepresent the logical sequence of program logicCopyright © 2012 Pearson Education3-15Document FlowchartCopyright © 2012 Pearson Education3-16Document Flowchart (cont’d)Copyright © 2012 Pearson Education3-17System FlowchartCopyright © 2012 Pearson Education3-18Program FlowchartCopyright © 2012 Pearson Education3-19