DFD Study Sheet - 2. 3 to 6 groups 3. Data flows from...

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Data Flow Diagram Rules Groups Groups on chronologically sorted table must translate into the level zero DFD correctly. Rules for Context Diagram 1. One Circle or process. Label – do not number. 2. Include external entities – no internal entities no files must have a label 3. Data flows must be labeled Direction of the data flow must be correct No crossed lines 4. All data flows and External Entities in context diagram should be included in the Level 0 Diagram. Level 0 DFD 1. Must match table with chronological groups to DFD
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Unformatted text preview: 2. 3 to 6 groups 3. Data flows from smaller number to higher number (i.e. 1.0 2.0, NOT 2.0 1.0). 4. Label lines 5. 6. For each group, make sure input is correct. 7. Check outputs, and when it is used by the next process draw line (data flow). 8. To update a file, you must draw lines back into the process bubble. Drawing a line from file to file (directly) is incorrect. 8. Creating data storage for the first time (Temporary Storage) 9. Updating (Permanent Storage)...
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DFD Study Sheet - 2. 3 to 6 groups 3. Data flows from...

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