Answer to Question #201569 in Mechanical Engineering for Atulkumar

Question

The owner of a video store has contacted you to develop a system to keep track of videos and rentals. He feels that with the growing number of customers, such a system will greatly help in managing accounts and providing better customer service.

 

Derive the process model that you think will be most appropriate for the above situations. Also list your reasons for choosing the process model.

Answer 1

The Data Flow Diagram (DFD) visualises how information (data) flows through a system. You can identify what information is supplied by and supplied to someone who participates in system operations, what information is needed to complete the processes, and what information needs to be kept and accessible by developing a Data Flow Diagram. The Data Flow Diagram is widely used in software development. Using a movie rental system as an example, this article discusses and explains Data Flow Diagram (DFD).

DFD context

A context Data Flow Diagram for a movie rental system is shown in the diagram below. It includes a process (shape) that reflects the system being modelled, in this instance, the "Video Rental Store." It also depicts the external entities or participants who will interact with the system. There are two external entities in this example: Customer and Manager. There are data flow connectors between the process and the external entities, demonstrating information exchange between the client and the system.

A data flow model's entry point is the context DFD. The diagram is simplistic since it just shows one operation and no data storage.

DFD Level 1

The level 1 DFD, which is the breakdown (i.e. break down) of the video rental system illustrated in the context DFD, is depicted in the diagram below. After you've gone over the diagram, we'll go over some of the main principles that are based on it.

Three operations, two external entities, and two data storage are shown in the Video Rental System Data Flow Diagram. Even though there is no design rule governing the placement of shapes in a Data Flow Diagram, we like to put processes in the centre and data storage and external entities on the sides to make it simpler to understand.

According to the diagram, a Customer submits a Video request to the Rent Video procedure. The Rent Video procedure also receives video information from the Video Library data repository. Consequently, the procedure generates a Customer Bill and saves the Rental information in the Rental data store.

By supplying video and rental information, a customer can Return Video. The video information is saved in the Video Library data store, and the rental information is saved in the Rental data store. As a result, the Customer receives a Return Receipt. The Data Flow Diagram does not imply that the receipt is given due to the Return Video procedure, despite what we mentioned. Our common sense led us to read the diagram in the way that we naturally understood it. The graphic, strictly speaking, merely shows us that the Return Video process accepts Video and Rental information and produces Video information, Rental information, and a Return receipt in that sequence.