Chapter 3 Systems Documentation Techniques Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-1

Learning Objectives  Prepare 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 Education, Inc. publishing as Prentice Hall 3-2

What Is Documentation?  Set of documents and models  Narratives, data flow models, flowcharts  Describe who, what, why, when, and where of systems:  Input, process, storage, output, and controls Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-3

Why 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 understanding  Sarbanes-Oxley states that management:  Is responsible for internal control system  Is responsible for assessing the effectiveness of the IC System  Both management and external auditors need to document and test IC System Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-4

Data Flow Diagrams  Graphically describes the flow of data within a system  Four basic elements Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-5 Entity Process Data Flow Data Store

Entity  Represents a source of data or input into the system or  Represents a destination of data or output from the system Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-6

Data Flows  Movement of data among:  Entities (sources or destinations)  Processes  Data stores  Label should describe the information moving Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-7

Process  Represents the transformation of data Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-8

Data Store  Represents data at rest Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-9

Data Flow Diagram Levels  Context  Highest level (most general)  Purpose: show inputs and outputs into system  Characteristics: one process symbol only, no data stores  Level-0  Purpose: show all major activity steps of a system  Characteristics: processes are labeled 1.0, 2.0, and so on Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-10

DFD Creation Guidelines  Understand the system  Ignore certain aspects of the system  Determine system boundaries  Develop a context DFD  Identify data flows  Group data flows  Number each process  Identify transformational processes  Group transformational processes  Identify all data stores  Identify all sources and destinations  Label all DFD elements  Subdivide DFD Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-11

Flowcharts  Use 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 Education, Inc. publishing as Prentice Hall 3-12

Flowchart Symbol Categories  Input/Output  Processing  Storage  Miscellaneous Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-13

Flow Chart Symbol Categories  (cont’d) Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall

Types of Flowcharts  Document  Illustrates the flow of documents through an organization  Useful for analyzing internal control procedures  System  Logical representation of system inputs, processes, and outputs  Useful in systems analysis and design  Program  Represent the logical sequence of program logic Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-15

Document Flowchart Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-16

Document Flowchart (cont’d) Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-17

System Flowchart Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-18

Program Flowchart Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 3-19