The key concepts of the data flow diagram are the following. In addition to PowerDesigner's standard palette, a Data Flow Diagram tool palette is available to let you rapidly create objects specific to the diagram type:
Concept |
Tool |
Gane & Sarson |
Yourdon |
Description |
---|---|---|---|---|
Process |
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Location where data is transformed. See Process. |
Flow |
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Oriented link between objects, which conveys data. See Flow. |
Data store |
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Repository of data. See Data store. |
External entity |
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Source or destination of data. See External entity. |
Split/Merge |
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Splits a flow into several flows or merges flows from different sources into one flow. See Split/merge. |