Data Flow Diagram

In: Computers and Technology

Submitted By awfulsmokey
Words 6419
Pages 26
Data Flow Diagram Tutorial

Objectives

After completion of study of this unit you should be able to:

Describe the use of data flow diagrams

Produce a data flow diagram from a given case study including different levels

Distinguish between the different categories of data flow diagrams

1. Introduction

1.1 CASE tools

1.2 Development and purpose of Data Flow Diagrams

2. Components of Data Flow Diagrams

2.1 Components

2.2 Hints on drawing

2.3 Data flows

3. Developing Data Flow Diagrams

3.1 Introduction

3.2 Context diagram

3.3 Level 1 Data Flow Diagram

3.4 Lower levels of Data Flow Diagrams

3.5 Check list

4. Categories of Data Flow Diagrams

4.1 Physical

4.2 Logical

4.3 The relationship between logical and physical Data Flow Diagrams

5. An example of the development of a Data Flow Diagram

6. Process models

7. Summary

8. Activities

9. Bibliography

10. Commentary on activities

1. Introduction

This unit deals with one of the major techniques for recording the requirements of a user for a new computer application. An initial diagram is constructed to show the processes which are being implemented in an existing system. The diagram helps to show how information is used to produce the functions that are required by the current system. It also shows what information is provided to the system and what information is provided form the system. Other benefits include the documentation of who is using the system and what data will be stored. By careful construction of the DFDs (data flow diagrams) the boundaries of the system to be built may be clearly identified. This helps to clarify what will and what will not be constructed. It will also show the interaction that may be required with other…...

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