Four data dictionary categories should be developed to promote the understanding of the data of the system: data flows, data structures. data elements, and data stores.

look at the above DFD. The example is to add a new customer order and to update the customer and item files. The external entity is customer (not seen on the DFD).

a) Write the data flows that appears on the DFD. Mention which data flows are input and which data flows are output.

(b) Write the data stores that appear on the DFD.

(c) How many processes are on the DFD. Write the names of the process(es).

D1 Item Masteir Item IDItem Record Customer Order Qrder Record , Add D2 Order Master Customer Order Customer Record D3 Customer Master