Issuing Item from Departmental Store
This system is a sub system of Departmental Store Management System. It can work as a single function. This function/system takes inputs form customers. A customer gives item_name and item_quantity as inputs. At the same time the system check the availability of the item and ask for payment from customers. Customer pays and receives bills. Bills are generated by the system. Vendor in this system acts as secondary users they also give item_name and item_quantity as inputs to the process, confirms the payment made and process for bills to be generated.
This Data Flow Diagram was taken directly from my notes so if you have any problems in understanding it, you are kindly requested to leave comment below.
A simple context diagram of this system can be drawn as below with the general symbols used in DFD. This context diagram describes the flow of inputs to the system. A process is named as Issuing Items. External entities such as customer and vendor take part in this system.
Figure 1 Context diagram of DFD Issuing Item from a departmental store
Similarly, Level 1 DFD is drawn to explain the system in detail. Above context diagram is broken into small functions to give a prefect vision how the system works. For this system, we broke the process into four different functions. For the storage of data we have used three different data stores, now external entities are customer, vendor/cashier and manager.
Figure 2 Level-1 DFD for Issuing Item from a departmental store
Description of Level – 1 DFD
The whole system is initialized by the action of Customer (external entity). In Level – 1 DFD there are four processes, namely Check Item Rates, Create Bills, Update Sales and Generate Report. Data are stored in Data Stores namely, Items_db, Sales_db, and Bills_db. As in a departmental store when a customer wants to buy something s/he first looks at the item rate and then decides whether or not to buy that good. In same way, our system also takes the item_name and item_quantity as inputs form customers and checks for the item rate and calculate the sum, to check item rate system fetches data form Items_db data-store. This is done by Check Item Rate process. When an item is to be issued, the system checks on the data store for the availability of items. Customer pays for item issued, when payment is confirmed by cashier then bills are created by Create Bills process. Sales are updated by Update Sales process. Lastly, reports are generated by Generate Reports Process. Reports are to be checked by head of store/ or manager.
Different from Issuing books from Library, this data flow diagram will surely help you when developing Departmental Store Management System and it’s idea will definitely help in designing similar other DFDs. In you have any problem understanding this DFD you can leave it in comments below.