[Year 12 SofDev] A DFD theory challenge!

[Mark KELLY]

Hi all. As I ponder the Mexican Cantina detailed example of SD U4O1 in the
study design, I find the DFD increasingly interesting.

The case study says that the student's mobile software (call it system 1)
writes an order to a text file.
The other software (call it system 2) reads the text file and transmits it
to the kitchen.

The question is: Is the text file a 'data store'?  What constitutes a data
store?
Does it need to be both written to and read to qualify as a data store?
Does it need to be written/read by the *same* system?
Or can it be read/written by 2 systems?
If it's only written by system1, and then left somewhere to be read by
system 2, does it still count as part of system 1?

Therefore: Should the text file be shown as a data store in the DFD?
Should system 2 be shown as an external entity getting input from the text
file?
Will Saint Kilda get into the final 8 this season?

Draft DFD attached.
-- 
Mark Kelly
Manager of ICT, Reporting, IT Learning Area
McKinnon Secondary College
McKinnon Rd McKinnon 3204, Victoria, Australia
Direct line / Voicemail: +613 8520 9085, Fax +613 9578 9253
kel at mckinnonsc.vic.edu.au
VCE IT Lecture Notes: http://vceit.com
Moderator: IT Applications Edulist <http://www.edulists.com.au/>

Want a good time? Call 0112358. Ask for Mr Fibonacci.
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