I have an example for a DFD for a patient information system implemented in a certain hospital. The below figure, represents the overview diagram (level 0-diagram, if we consider that the first level is the context diagram then the second level is level 0 diagram and so on):
In this system, patients can search and make appointments. I try to understand the data flow that is labeled
patient name and that is directed from the process
Make appointment to the database
Patients (see yellow hightligh in the diagram).
I don't understand why we have this flow in our system: In which scenario would the process
Make appointment send to the database
patients the patient name ? Shouldn't the patient name already be sent by the process maintain patient info?