Make a data flow diagram involved in a petrol retail branch. Factor in relevant data modeling relationship. (500 words)

- Present data flow diagrams (DFDs) as an essential tool for translating process into visual form of data flows, data stores into form. Enumerate that this was a context basal DFD you will present.

- Exhibit the context flow chart within which the processes, i.e. order fuel, pay, deliveries, and roster, are included. Show the majors inputs and outputs.

- Select 2 of the main steps and split them to a more detailed form DFD that embodies sub-processes, data store and data items.

- Talk about data modeling with requirement such as for customers, orders, payments and entities together with the relations between them. Present sample ER diagram available.

- Emphasizing this, DFDs and data modeling comprise rigorous approaches of gathering system needs for development.