Data Flow Diagrams
The following text is derived from the Data Flow Diagram entry in the online Wikipedia.
A data flow diagram (DFD) is a graphical representation of the "flow" of data through an information system. A data flow diagram can also be used for the visualization of data processing (structured design). It is common practice for a designer to draw a context-level DFD first which shows the interaction between the system and outside entities. This context-level DFD is then "exploded" to show more detail of the system being modeled.
Data flow diagrams were invented by Larry Constantine ... based on Martin and Estrin's "data flow graph" model of computation. ( They ) are one of the three essential perspectives of Structured Systems Analysis and Design Method SSADM. The sponsor of a project and the end users will need to be briefed and consulted throughout all stages of a system's evolution. With a dataflow diagram, users are able to visualize how the system will operate, what the system will accomplish, and how the system will be implemented. The old system's dataflow diagrams can be drawn up and compared with the new system's dataflow diagrams to draw comparisons to implement a more efficient system.
Developing a DFD helps in identifying the transaction data in the data model.
Access Diagram | Diagram Toolbox: More Tools | Data Flow Diagrams
Data Flow Diagrams in Enterprise Architect
Within Enterprise Architect, you can develop Data Flow diagrams quickly and simply through use of an MDG Technology integrated with the Enterprise Architect installer. The Data Flow diagram facilities are provided in the form of:
|·||A Data Flow diagram type, accessed through the New Diagram dialog|
|·||A Data Flow Diagram page in the Toolbox|
|·||Data Flow element and relationship entries in the Toolbox Shortcut Menu and Quick Linker|
Data Flow Diagram Toolbox Page
Data Flow Diagram Appearance
When dragged onto a Data Flow diagram, the elements and relationships have the following appearances:
To preserve the simplicity and readability of the diagram, you cannot display the element compartments on the diagram.
A Context diagram is a top-level Data Flow diagram that has just one Process element representing the system being modeled, showing its relationship to external systems.
Disable Data Flow Diagrams
If you prefer to not use Data Flow Diagramming in Enterprise Architect, you can disable it (and subsequently re-enable it) using the MDG Technologies dialog (Extensions | MDG Technologies).
|·||Data Flow Diagram (Online Resource)|
Learning Center topics
|·||Alt+F1 | Enterprise Architect | Modeling Languages | Standard Profiles | Data Flow Diagrams|