Construct DFD


To construct a data flow diagram:



  • Maintain a consistent level of detail with between five and nine symbols per page.  Data flow arrows do not cross each other.
  • Label your data flow arrows first - these are the most important items - and your processes circles last
  • Process circles may have several arrows flowing into and out of them
  • An arrow from a data store always go to a process.  An arrow to a data store always comes from a process
  • Include a descriptive narrative that explains the data flow diagram


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