Chapter 11 What is DFD and Types Explain in Details

CHAPTER 11

DFD

(DATA FLOW DIAGRAM )

DFD :- Data flow diagram and also known as “Bubble Chart”

DFD show the flow of data between various elements of a system in graphical form, It also express the requirements of the system and show how the content current system is implemented.

It is gives an overview of what data a system process, what transformations are being performed, what data are stored, what results are produced and where they flow.

It is graphical is natural makes, it’s a good communications tool between user and system design(System Analyst)

DFD is easy to understand and quite effectives tool for communications (between user and system analyst) when required design it’s not clear.

It requires a large number of iterations for obtaining the most accurate and complete solution.

Basic elements of DFD/ Components of DFD:- It means used symbols in designing the DFD are:-

Types of DFD:-

1. Logical DFD :- It Show how data flow in a system, It describes what data is moved from one entity to another. It focus on what happen in the data flow. It show how system works not, how the system can be implement. It is implemented independent.

2. Physical DFD :- It show how data flow is actually implemented in the system. It describes how data is moved from one entity to another. It is implementation dependent.

Levels of DFD :-

There are mainly three levels.

1. 0 Level DFD

2. 1 Level DFD

3. 2 Level DFD

Explain all level :-

1. ) 0 Level DFD :- It show the system as a single process with it’s relationship to external entities, it’s represented the entire system a single process input data and output indicated by incoming / outcoming arrows, It is also known as fundamental system model and it show only abstract video.

2. ) 1 Level DFD :- In 1 level DFD, we decompose the context level DFD (0-level DFD) into multiple component and define each components in details.

3. ) 2- level DFD :- In 2-level DFD we decompose the 1-level DFD into more details and define each necessary details about system functioning properly.

Some Extra example pending :-

Comments

Assignment of ITA/ Information Technology and Application BCA- Technology369kk

Q1. What is computer Explain basic computer architecture and Difference components. 2. Discuss the use of memory in computer system, Explain memory hierarchy in details. 3. What is software? Explain difference types of software with explain. 4. Write short notes on the given:- (I) Internet. (II) LAN (Local area network ) (III) Search engine (IV) Web browser Q 1.What is computer Explain basic computer architecture, Difference components of computer. Computer :- Computer is defined as an electronic device that takes input data and instructions from the user and after processing them, it generates useful and desired output quickly. A computer is designed to execute applications and provides a variety of solutions through integrated hardware and software components. It is fast and automatic device. It works with the help of programs and represents the d...

C++ and Java Practical All Questions Answers - BCA -Technology369kk

C++ and Java In this post see most important questions for practical questions given by college all questions with answers . Guys I want to say that this is only for suggested post for your practical please request to you change same alphabets, words or anything methods name and variables name because if you write all words same then this is copy paste for another peoples. Used Topics: Keywords, Variables, Condition Statements, Function , Array, Structure, Pointer. In OOPs, Class and Objects, Constructor, Poly morph, Encapsulation, Access Specifiers, Inheritance etc. So, Without Time Lose Come to the Points, let's go start Now: ************************************************************************* C++ 12 ...

Assignment of PMO (Principal of Management and Organization) - Technology369kk

** Assignment Of PMO ** Agenda: - 4 Questions discuss in this post. Question 1. Write a d etails note on selection why it Called. negative process. Question 2. Write a details note on 'span of control. Question 3. Planning is an essential process, do you agree ? Discuss Question 4. Write a note on management function. Q 1. Write a d etails note on selection why it called negative process. Ans :- Selection is the process of choosing the most suitable candidates out of the several candidates available. Selection is a negative process because there may be more rejected then those selected in most of the candidates that is called selection is a negative process. → Selection process has the following steps:- [ A .] Screening of applicants - Based on the screening of applicants only those candidates. It Called further process of selection. Who are found eligible for the job Standards of the the organization. [ B .] S...

Search This Blog