Data Flow Diagrams – Simply Put!

Learn about Data Flow Diagrams (DFDs), Context-level DFDs, and Rigorous Physical Process Models (RPPM), what they are, why they are important, and who can use them.

Use Data Flow Diagrams to Visualize Workflows

An old Chinese proverb says, “A picture is worth a thousand words.” In the world of Information Technology (IT), we maintain that it may even be worth a whole lot more. For most people, it is difficult or impossible to envision a process flow, especially when someone else is describing it.

Understanding current workflows, however, is critical to defining a future IT solution. Just as critical is understanding how data is created and consumed throughout the workflow.

To truly understand problems inherent in a business process or workflow, you need to help the practitioners visualize what they do. Visualization lets them identify better ways of working that remove current restrictions.

Data Flow Diagrams are phenomenal tools for visualization. Working with business experts, you can help them identify problems and inefficiencies they don’t even know they have. These are not people problems; they are process problems. Understanding when and how to create and use Data Flow Diagrams will help you discover and capture the requirements for improving the use of information technology.

Why Should You Take this Course?

In “Data Flow Diagrams – Simply Put!”, you will learn the benefits of process visualization for the business community, for the one wearing the BA hat, for those tasked with developing the solution, and ultimately for the entire organization.

You will also discover how DFDs are powerful tools for recognizing and eliminating two of the major problems that haunt IT projects, namely Scope Creep and Project Overruns caused by late project change requests.

This book uses a concrete business scenario to present a simple, easy-to-learn approach for creating and using Data Flow Diagrams depicting workflow and data manipulation from interviews with Subject Matter Experts.

You will learn how to create a Context-Level Data Flow Diagram and explode relevant process(es) to reveal the nitty-gritty detail (i.e., individual process and data specifications) that developers need to create IT solutions that the business community needs.

This book answers the following questions:

• What is a Data Flow Diagram (DFD)?
• What is a Rigorous Physical Process Model?
• What is a Context-Level DFD?
• Why should I use Data Flow Diagrams?
• What symbols can I use on each type of diagram?
• How can I drill down into a process?
• How can I show internal processes and flows that produce the results?
• What does balancing a Data Flow Diagram mean and what is the business value?
• What is the most efficient approach to balancing a DFD?
• What business value do process specifications offer?
• How can I express detailed specifications for processes and data?
• What is “metadata" and why do you need it?
• What does a fully balanced DFD look like?
• What value does a DFD fragment provide?

Regardless of your job title or role, if you are tasked with communicating a workflow or functional requirements to others, this book is for you.

• Product Owners
• Business Analysts
• Requirements Engineers
• Business- and Customer-side Team Members
• Agile Team Members
• Subject Matter Experts (SME)
• Project Leaders and Managers
• Systems Analysts and Designers
• AND “anyone wearing the business analysis hat”, meaning anyone responsible for defining a future IT solution

• Preface
• About the Authors
• Introducing Data Flow Diagrams (DFDs) for the Business
  • Business Processes, Data Flows, and Value Chains
  • What is a Data Flow Diagram and Why Do You Need One?
• Modeling the Flow of Material and Data
  • Introducing Rigorous Physical Process Models to Identify Stakeholders
  • Drawing an RPPM Using Identified Stakeholders and Interview Notes
• Visualizing Project Scope
• How to Identify the "Right" Internal Processes for a DFD
  • Representing Increasing Levels of Detail Using a DFD
  • Identifying Candidates for Internal Processes
  • Selecting the Appropriate Processes to Include on the Detailed DFD
• Drawing a Detail Level DFD
• Balancing the Levels Ensures Completeness
  • Balancing Data Flows from the Higher to the Lower Level
  • Balancing Data Flows from the Lower to the Higher Level
• Creating Detailed Process and Data Specifications
  • Defining Functional Primitives
  • Capturing Metadata for Critical Business Data Elements
• Horizontal Balancing Reveals Missing Data Elements
  • Defining and Justifying the Value of Horizontal Balancing
  • A Walk-through of Horizontal Balancing
• The Business Value of Data Flow Diagrams
  • Creating and Using DFD Fragments vs Completely Balanced DFDs
  • Summary
  • What Should You Do Next?