ITEC 3010 Chapter Notes - Chapter 1-10: Data Flow Diagram, System Context Diagram, Data Store
Document Summary
Data flow diagram: equally to erd, it is a very simple one, big difference in traditional and structural approach is that, in traditional approach all models are simple, easier to visualize. Stages: process, basically the instructions, the data flow, external agent, data store and real-time link. Other diagrams show the processing at really higher level or a very low level. Contexts diagram: a data flow diagram that has one single process which is numbered by 0 . Data flow diagram fragments: defining one fragment for each event, all the processes have to be numbered but not in sequence, not necessary, one doesn"t depend on the previous one, refining is at later stages. For example: from student, requests enrollment and gets schedule, to enrolling student process then to the storage which are student, offered course and course enrollment, then we move to next fragment like faculty members and so on.