System Analysis and Design PDF

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Accoarding to the syllabus of Saurashtra University Published by : Bharat & Company and useful for the students of S.Y.B.C.A(Sem.-3) Dr. Yagnik Road, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Rajkot. - 360 001 SYSTEM ANALYSIS & DESIGN Cell - 99988 01215 AND Autho.Dealer: Bharat Book Stores, ...

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Accoarding to the syllabus of Saurashtra University and useful for the students of S.Y.B.C.A(Sem.-3) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

SYSTEM ANALYSIS & DESIGN AND

SOFTWARE ENGINEERING

Published by : Bharat & Company Dr. Yagnik Road, Rajkot. - 360 001 Cell - 99988 01215 Autho.Dealer: Bharat Book Stores, Opp. D.H.College, Dr. Yagnik Road, Rajkot. - 360 001 Ph. (0281) 2465148/2481545

© All Rights are reseved by Publisher. First Edition : 2007 Rs. 80/-

No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying (Zerox), recording or otherwise, without the prior permission of the Publisher, Otherwise the publisher have to take some Legal Acction.

VISHAL VARIA

Bharat & Company (The Educational Books Publisher)

Printed by :

Umiya Ofset Ahmedabad.

PREFACE

About the Author

Saurshtra University has designed versatile courses like BCA and PGDCA. This courses focus on the development of student in the field of information technology. This field is every expanding and developing. To keep pace with the global requirements and challenges we must develop ourselves uptodate in this field. To take the students to the international platform and prepare them to face the challanges of information technology (the next generation) Saurashtra University has not only introduced but also developed such courses in the favour of students. By being in BCA for three years the student almost passes through all the areas of information technology viz. programming, web-designing, software analysis, webprogramming, embedded programming, etc. Networking is also one such important area where students can focus on and develop themselves. To cope up with the industry and bring good results with the University Exams one must have good tools/weapons to fight competition. With this book, we are trying to give such tool/weapon to students so that they can prepare themselves to face the challenges of the future competition. The book is desinged in the way that is most understanding and comprehensive to students and their grasping power. The language used by the author is simple and easy to understand. The topics are divided into subtopics and points that are easy to grasp and remember. The book focuses on the minute details of the chapters and their topics as per the syllabus weightage. Important questions are also summerized at the end of each chapter that will enable the students on the exact topics that are important from the chapter and for scoring marks. The book also contains appropriate graphics and examples for better understanding. This book will also be useful as the last minute revision guide to the exam as the topics are represented in pointwise fashion for easy rememberance. In short, through this book we are trying to fill the requirement of students for the subject material for SYSTEM ANALYSIS AND DESIGN AND SOFTWARE ENGINEERING subject. This is our maiden project and is bound to contain some errors non-technical in nature. We regret such errors if any and would like to have your feedback on this book. The feedback form is included in this book after this page. We, wish you all the very best to for the subject for University Exams. Vishal Varia

The author, Mr. Vishal Varia, is in the field of information technology and working as a Visiting lecturer with various prestigious institutes in the town since last eight years. He is an able professor who proclaims the focus of students to the topic and is popular among them. It is his esteem desire to reach to those students, who cannot take the benefit of his lectures, via the medium of his books. He has found that there are plenty students who can make good career if personal interest is taken by their respective faculties. A student who is in the college and about to start his career life not only requires technical knowledge but also a vision and proper guidance that can establish him/her in a sound position. The author has also made a point to guide students via his books and provide them a good vision for their better tommorow. We are proud that such persons are associated with us and also co-ordinate and co-operate with our goal to provide students a vision about his/her future career. We wish the author all the very best and expect a continuous association with him. We also wish that the author also comes out with his other titles that help students to develop other topics as well. We also wish all the best to all those students who are preparing for their exams in Universtiy. The Publisher (Ketan Popat)

ACKNOWLEDGEMENT For the complition and compilation of this project there has been contribuition from many people. We take this opportunity to show gratitude towards all those people who has contributed towards the complition of this project knowingly and unknowingly. We would first like to express our deep gratitude towards the Saurashtra University and the HOD of Computer Science Department Dr. N.N.Jani for incorporating such dynamic and technical courses in the sysllabus. Dr. N.N. Jani has always been a source of inspiration in person to the author. We are also indebted to the students of BCA of the University of all the colleges accross Saurashtra who have inspired us for the development of this book. We are thankful to all the authors of publications in this field for giving inspiration to the author indirectly. We show our sense of gratitude towards all the person associated in the compilation of the book the operator who has spend his valuable time in compiling the project, the editor of the book for successfully putting in the fashion in which it is there now. Last but not the least, we are thankful to the friends and family members for cooperating with us during this compilation. Inshort, we thank all the persons who have knowingly or unknowingly contributed to the development of the project.

Dedicated to The Students of BCA Saurashtra University.

The System of Learning &

The System of Preparing

understanding this Subject

this Subject for Exam

System Analysis is a completely theoretical subject. To learn a theoretical subject is not easy. One must have greater concentration and patience to learn and understand a theory subject. However SAD is not a pure theory subject. The principles of SAD are practical in nature. One easily implement the concepts of SAD into any object and get desired result. One must follow the below mentioned points to better understand this subject:  One must not try to mug up SAD. This would be injustice to the topic. Instead one must try to feel the topic.  Try to find system in every moment, every word, every transaction, every action, every function, every event, etc.  Every single thing you will see you will find has a system of its own. The nature, the Govt. officials, the banking, teaching, learning, gaming, etc.  If you do not follow the system of the transaction and action then you would stand nowhere. The system would not respond you your desired results.  If you do not follow the system of learning and remembering then you would not get your desired result in the exam.  Try to feel the subject. Empathize the topic in your day to day life and see the difference.  This topic is not exactly for learning it is for application and implementation.  Imbibe the principles of SAD while learning the topic of SAD and you will find the topic very interesting.

Please follow these steps in order to remember this topic for exam:  Divide the topic into its four parts  Preface  Introduction - Definition  Body  Conclusion  Create and Quote examples for each topic you learn and mention. You will find genuine examples in each of the topics of SAD.  Elaborate those examples and explain why you have quoted them here.  Draw a diagram if possible in a neat and tidy fashion.  Explain the diagram in a step by step fashion.

Feed Back Form

Syllabus CS14 : SAD&SE

1. INTRODUCTION

Name : ____________________________________________ Address : __________________________________________ ___________________________________________________ ___________________________________________________ Contact No. : _______________ College : ___________________________________________ Stream : ___________________________________________ Year : FY/SY/TY___________________ Please give your honest opinion about the book. [Tick whatever applicable] 1. How do you find the content of the book? a) Useful and Exam Oriented _______ b) Useful but not Exam Oriented _______ c) Exam Oriented but not useful _______ 2. How do you find the language of the book? a) Easy to understand _______ b) Somewhat hard to grasp _______ c) Difficult _______ 3. How do you feel about the layout of the book? a) Good __________b) Easy to read ________ c) Improvement required ____________ 4. Feel free to quote your own remarks here. ____________________________________________________ ____________________________________________________ ____________________________________________________ ____________________________________________________ ____________________________________________________ ____________________________________________________

-: Please photocopy this form and post it to :-

Bharat Book Stores Opp.D.H.College, Dr. Yagnik Road, Rajkot.

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What is System & Sub System? Characteristics of System Information System Categories of Information System. - Transaction Processing System - Management Info. System - Decision Support System What is System Analysis & Design? Responsibilities of System Analyst Different types of users. What is SDLC & its Stages

2. PROJECT SELECTION -

Reasons for Project Proposal Sources of Project Request Project Review & Selection Feasibility Study.

3. REQUIREMENT ANALYSIS - What is Requirement Determination? - Activities in Requirement Determination. - Fact-Finding Techniques - Interview - Questionnaire - Record Review - Observation - Tools for Documenting Procedures & Decisions - Decision Tree - Decision Table SRS Document

4. STRUCTURED ANALYSIS - Dataflow Diagram - Data-dictionary

5. INPUT DESIGN & OUTPUT DESIGN -

Objectives of Input Design Various Coding Techniques Input Validation What is Output? Types of Output. Types of Output Presentation. - Tabular - Graphics

6. DESIGN OF FILES - Basic File Terminology - Types of File - Master File - Transaction File - Table File - Report File

- Methods of File Organization - Sequential Organization - Direct-Access - Indexed Organization

7. SOFTWARE DESIGN - Top-Down Structure of Modules - Coupling & Cohesion., Span of Control-Fan-ln,Fan-out - Design & Documentation Tools - Structured -Chart - HIPO

8. SOFTWARE TESTING, & QUALITY ASSURANCE & IMPLEMENTATION - Testing Methods - Unit Testing - Black-Box Testing - White-Box Testing - System Testing - What is Software Quality? - ISO9000 (Introduction Only) - Conversion Method

9. INTRODUCTION TO SOFTWARE ENGINEERING -

Differe nt Type of Software Applications Software Myths and Reality Ge neric View o f So ftware Engineering Software Process & Different Process Models (Sequential, RAD, Incremental, Spiral)

10. SOFTWARE PROJECT MANAGEMENT - Project Management (3Ps- People, Problem, Process ) - Project Planning - Sizing (Size & Function- Oriented Metrics) - Estimation (LOG, FP) - Make-Buy Decision Risk Management - Different type of Risks (Product-size, Business, Customer, Staff, Process, Technology) - RMMM Plan

11. SOFTWARE DESIGN - Introduction to OOA & OOD - What is Object, Attributes, State, Behavior ? - Benefit of OOD

INDEX Page No. 1. Introduction 1 2. Project Selection

29

3. Requirement Analysis

37

4. Structured Analysis

53

5. Input Design & Output Design

71

6. Design of Files

95

7. Software Design

99

8. Software Testing, & Quality Assurance & Implementation 105 9. Introduction to Software Engineering

111

10. Software Project Management

127

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Saurashtra University Question Papers of previous years.

144

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1.

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INTRODUCTION

  What is System & sub system /  Characteristics of System /  Information System /  Categories of Information System - Transaction Processing System - Management Info System - Decision Support System /  What is system Analysis & Designing / Responsibilities of System Analyst / Different types of users. / 8. What is SDLC & its Stages   WHAT IS SYSTEM & SUB SYSTEM ? The term system may be defined as set of inter related elements that operate collectively to accomplish some common purpose or goal. One can find may examples of a system. Human body is a system, consisting of various parts such as head, heart, hand, legs and so on. The various body parts are related by means of connecting networks of blood vessels and nerves. This system has a main goal, which we may call “living”. A business is also a system where economic resources such as people, money, material, marketing, machines, etc. are transformed by various organizational processes into goods and services. A computer based information system is also a system, which is a collection of people, hardware, software, data and procedures that interact to provide timely information to authorized people

SAD & SE by Vishal Varia

Introduction

3

who need it.

2. CHARACTERISTICS OF SYSTEM (a) Predetermined Objective: All systems have predetermined objectives. If any organization is working without predetermined objectives then it is not called a system. The objective is the goal of the system. It is the purpose of the system for which it is functioning. If the purpose of the system is not achieved then the system will fail. The system is said to be successful and in working condition only if it achieves the predetermined objectives. System Education System Automobile system Human body Business system

Objective To convert empty brain to developed minds To transport goods or people from one place to another To live and be lively. To achieve profit and maintain existence in the business world.

(b) Set of Components: A system is not standing alone. It is a system because it contains a list of components inside it. A system is a group of components, if any component is missing then the system will fail. A system cannot work unless the components inside it do not work. Thus a systems existence is a result of the work of the components of the system. (c) Set of Process: A system is not only the set of components taken together but is also the process of the components. If we gather the raw material then the product is not going to get formed unless some process is applied to the raw material. Like wise collecting bricks, water, cement, worker and other component will not make the building (system) ready unless the process is applied to it.

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SAD & SE by Vishal Varia

System Education

Human Body

Component Teacher Student Institute Stomach Lungs

Process Teaching Process Learning Process Admission Process Digestion Process Purification Process

(d) Interrelated and Interdependence: All systems consist of interrelated and interdependent elements or components. For example, our biological system contains bones, organs and different biochemical. Similarly a business system consists of organizational structures, people and other equipments, working together to earn profit. All the components are interrelated with each other and they are interdependent on each other. For example, the blood carries oxygen from lungs to other parts of the body. That is blood, lungs, and other body parts are interrelated and interdependent on each other. (e) Subsystem: A System can be further divided into sub system, each of which have their own components and process. In practical world like components make one system which is a part of sum super system. This can be further easily be understood with the following table: System Human Body Business System

Automobile System

Education System

(f) Interaction:

Subsystem system, Circulatory

Digestive System, etc. Accounting System, Purchase and Sale System, Production System, Etc. Internal Combustion Engine, Fuel System, Weight Carrying System, etc. Teaching Subsystem, Admission System, Exam System, Etc.

Introduction

5

The way each component of a system functions with the other components of a system is called interaction. The different subsystem of a system interacts with each other to achieve the objective of the system. In a business system, for example, marketing subsystem must interact with production subsystem and payroll sub system may interact with personnel sub system. (g) Integration: Interrelationship and interdependence must exist among the components; this is referred to as integration. It is said for a system that the “whole is greater than the sum of the parts”, i.e. the components of a system work together to produce an effect which is greater that the sum of the effect which is greater than the sum of the effects of its components taken separately. The work done by individual sub system is integrated to achieve the central goal of the system. The goal of individual sub system is of lower priority than the goal of the system as whole.  Components of the System:

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SAD & SE by Vishal Varia

The system contains the following components: 1. Input 2. Process 3. Output 4. Control 5. Feedback These are explained in detail in the later part of this chapter as components of Information System.  System Environment, Sub system and Supra System: System Environment All systems function within some sort of environment. The environment, like systems, is a collection of elements. These elements surround the system and often interact with it. For any given problem, there are many types of systems and many types of environments. Thus it is important to be clear about what constitutes of system and the environment of interest. The features that define and delineate a system, forms its boundary. The system is inside the boundary, the environment is outside the boundary. In some cases, it is fairly simple to define what is part of the system and what is not. In other cases, the person studying the system may arbitrarily define the boundaries. Some examples of boundaries are given in the following table. System Human

Automobile Production

Boundary Skin, hair, nails and all parts contained inside forms the system. All things outside is environment The automobile body plus tires and all parts contained within form the system Production machines, inventory or work in process, production employees, procedure etc. form a system. The rest of the company forms its environment

A system and its environment can be described in many ways. A subsystem is a part of a larger system, each sub system

Introduction

7

being delineated by its boundaries. The interconnections and interactions between the sub systems are termed interface. Interface occurs at the boundary and take the forms of input and output. A supra system refers to the entity formed by a system and other equivalent system with which it interacts. For example, an organization may be subdivided into numerous functional areas such as marketing, finance, manufac...