4.5.3 Data Flow Diagram
DFD is a graphical representation of the «flow» of
data through an information system. DFDs can also be used for the visualization
of data processing (structured design). On a DFD, data items flow from an
external data source or an internal data store to an internal data store or an
external data sink, via an internal process.
It is common practice for a designer to draw a context-level
DFD first which shows the interaction between the system and outside entities.
This context-level DFD is then «exploded» to show more detail of the
system being modeled. With a dataflow diagram, users are able to visualize how
the system will operate, what the system will accomplish and how the system
will be implemented. Dataflow diagrams can be used to provide the end user with
a physical idea of where the data they input , ultimately has an effect upon
the structure of the whole system from order to dispatch to restock how any
system is developed can be determined through a dataflow diagram. In my case
DFD will be the intermediate of analyst and user of this system how the
customers make order up delivering date.
4.5.4
Context diagram
Is a diagram that represents the actors outside a system that
could interact with that system, This diagram is the highest level view of a
system, similar to Block diagram, showing a possibly software-based, system as
a whole and its inputs and outputs from/ to external factors.
In our case, external entities are the customers who will need
the various services from the system, and the Administration office who will
request the reports.
v From customer to the system: the system will provide
information using online system and customer access it without changing
anything and customer choosing the product and send order to the system, the
system accept or refuse, when the system accept it send to him an invoice, the
customer pay according to the invoice after the system give to him delivery
date of the product ordered.
v From administrator to the system: administrator requests
reports to the system and the system provide the report requested.
The detail information is presented in context diagram
below:
![]()
Figure 2: Context
Diagram
4.5.4.1 DFD level 0 for
whole OOIS
![]()
Figure 3: DFD
level 0 for whole OOIS
4.5.4.2 DFD level 1 for
manage product
Figure 4: DFD
level 1 for manage product
4.5.4.3 DFD level1 for
manage customers
![]()
Figure 5: DFD
level1 for manage customers
| 
