1. Systems Analysis and Implementation
Management Information System
System Analysis and Implementation. MIS

2. System
The term system, is derived — the Greek word systeme (to combine). which means an organized relationship among functioning units or components.
A collection of components organized to accomplish a specific function or a set of functions.

3. CHARACTERISTICS OF A SYSTEM
Basically there are three major components in every system, namely
Input,
Processing
Output.

4. THE SYSTEMS DEVELOPMENT LIFE CYCLE
System Analysis and Implementation. MIS

5. SDLC
It is an organizational process of developing and maintaining systems.
It helps in establishing a system project plan, because it gives overall list of processes and sub-processes required developing a system.
Also called software development life cycle.

6. Phases of software development cycle
System study
Feasibility study
System analysis
System design
Coding
Testing
Implementation
Maintenance

7. Phases of system development cycle

8. A simple process for making lunch

9. System Study The system study is done in two phases.
The preliminary survey of the system is done which helps in identifying the scope of the system.
More detailed and in-depth study in which the identification of user’s requirement and the limitations and problems of the present system are studied.
A system proposal is prepared by the System Analyst.

10. The system study phase passes through the following steps:
problem identification and project initiation
background analysis
inference or findings

11. Repository Business Community Project Request Or Assignment 1
List Problems,
Opportunities,
and directives
Preliminary Problem Statement
Project Charter 2
Negotiate
Preliminary
Scope
Problem Statements
Statements of Project
Repository 5
Present
the
Project
And plan
Preliminary Problem Statement Scope
Statement of work Project Schedule and resource Assignments 3
Assess
Project
worth
Problem Statements with Scope 4
Plan the
Project
Project Plan
Project is worthy

12. Feasibility Study
It is basically the test of the proposed system in the light of its workability, meeting user’s requirements, effective use of resources and of course, the cost effectiveness.
The main goal of feasibility study is not to solve the problem but to achieve the scope.
In the process of feasibility study, the cost and benefits are estimated with greater accuracy.

13. Types of Feasibility Study
Technical
Economic
Motivational
Schedule
Operational

14. System Analysis
Analysis is a detailed study of various operations performed by a system and their relationships within and outside the system.
During analysis, data are collected on the available files, decision points and transactions handled by the present system.
Interviews, on-site observation and questionnaire are the tools used for system analysis.

15. The main points to be discussed in system analysis are:
Specification of what the new system is to accomplish based on the user requirements.
Functional hierarchy showing the functions to be performed by the new system and their relationship with each other.
Function network which are similar to function hierarchy but they highlight the those functions which are common to more than one procedure.
List of attributes of the entities - these are the data items which need to be held about each entity (record)

16. Cont…
All procedures, requirements must be analyzed and documented in the form of detailed data flow diagrams (DFDs), data dictionary, logical data structures and miniature specifications.
System Analysis also includes sub-dividing of complex process involving the entire system, identification of data store and manual processes.

17. System Design Most crucial phase in the development of a system.
Normally, the design proceeds in two stages :
preliminary or general design
Structure or detailed design

18. Preliminary or general design
The features of the new system are specified.
The costs of implementing these features and the benefits to be derived are estimated.
If the project is still considered to be feasible, we move to the detailed design stage.

19. Structure or Detailed design
At this stage, the design of the system becomes more structured.
Structure design is a blue print of a computer system solution to a given problem having the same components and inter-relationship among the same components as the original problem.
Input, output and processing specifications are drawn up in detail.
The programming language and the platform in which the new system will run are also decided.

20. Tools and techniques used for designing are
Data flow diagram (DFDs)
Entity relationship diagram
Context diagram
System flow charting
Input–Output chart

21. Coding
After designing the new system, the whole system is required to be converted into computer understanding language.
programmer converts the program specifications into computer instructions, which we refer as programs.
The programs coordinate the data movements and control the entire process in a system.

22. Testing
A test run of the system is done removing all the bugs, if any.
It is an important phase of a successful system.
The output of the test run should match the expected results.

23. Implementation
Implementation is the stage of a project during which theory is turned into practice.
During this phase, all the programs of the system are loaded onto the user's computer.
After loading the system, training of the users starts.

24. Topics for training are
How to execute the package
How to enter the data
How to process the data (processing details)
How to take out the reports

25. Strategies for running the system
Parallel run
Pilot run

26. Parallel run
Both the systems i.e. computerized and manual are executed in parallel.
Advantage
Manual results can be compared with the results of the computerized system.
Failure of the computerized system at the early stage, does not affect the working of the organization, because the manual system continues to work, as it used to do.

27. Pilot run The new system is installed in parts.
Some part of the new system is installed first and executed successfully for considerable time period.
When the results are found satisfactory then only other parts are implemented.
This strategy builds the confidence and the errors are traced easily.

28. Maintenance
It is necessary to eliminate errors in the system during its working life and to tune the system to any variations in its working environment.
The review of the system is done for:
knowing the full capabilities of the system
knowing the required changes or the additional requirements
studying the performance

29. SYSTEM DEVELOPMENT METHODOLOGIES
System Analysis and Implementation. MIS

30. What Is a Methodology? A formalized approach to implementing the SDLC
A series of steps and deliverables
Methodology Categories
Process-Centered
Data-Centered
Object-Oriented
Structured Design
Rapid Application Development
Agile Development

31. Prototyping
It is a comprehensive system , and does not include all requirements of the user.
Prototyping-based methodologies perform the analysis, design and implementation phases concurrently.
All three phases are performed repeatedly in a cycle until the system is completed.

32. Prototyping- When it is used
When identification of requirements is difficult.
When requirements may change during the development process.

33. Prototyping-based Methodology

34. Steps Identify the user’s basic information requirements.
Develop the initial prototype system.
Use of the prototype system, to refine the user’s requirements.
Revise and enhance the prototype system.
The steps 3 & 4 are repeated again and again till the prototype is refined to the satisfaction of the user.

35. Advantages Disadvantages
Because its iterative nature , it requires too much time, effort and money.
They are not complete systems and many details are not built in the prototype.
Due to frequent changes, management of the development process also becomes difficult.
Ability to ‘try out’ ideas without incurring large costs.
Lower overall development costs when requirements change frequently.
The ability to get a functioning system onto the hands of the user quickly.

36. Waterfall Development Methodology

37. Pros and Cons of the Waterfall Methodology
Design must be
specified on paper
before programming
begins
Identifies systems
requirements long
before programming begins
Minimizes changes to
requirements as
project progresses
Long time between
system proposal and
delivery of new
system

38. Parallel Development Methodology

39. Pros and Cons of Parallel Development Methodology
Reduces Schedule
Time
Still Uses Paper
Documents
Less Chance of
Rework
Sub-projects May Be
Difficult to Integrate

40. Tools and techniques used for designing are
Data flow diagram (DFDs)
Entity relationship diagram
Context diagram
System flow charting
Input–Output chart
1 - 40

41. Data Flow Diagrams (DFDs)
Data flow diagram (DFD) is a graphical representation of logical flow of data
Helps in expressing the system’s requirements ina asimple and understandable form.

42. DFD Symbols Process Data Flow Data Store Source/Sink (External Entity)

43. Process Work or actions performed on data (inside the system)
Labels should be verb phrases
Receives input data and produces output

44. Rule 1: Process
Can have more than one outgoing data flow or more than one incoming data flow

45. Rule 2: Process
Can connect to any other symbol (including another process symbol)

46. Process: Correct/Incorrect?

47. Data Flow
Is a path for data to move from one part of the IS to another
Arrows depicting movement of data
Can represent flow between process and data store by two separate arrows

48. Data Flow: Correct/Incorrect?

49. Data Store Is used in a DFD to represent data that the system stores
Labels should be noun phrases

50. Rule: Data Store
Must have at least one incoming and one outgoing data flow

51. Data Store: Correct/Incorrect?

52. Source/Sink (External Entity)
External entity that is origin or destination of data (outside the system)
Is the singular form of a department, outside organization, other IS, or person
Labels should be noun phrases.
Source – Entity that supplies data to the system
Sink – Entity that receives data from the system

53. Rule: Source/Sink
Must be connected to a process by a data flow

54. Source/Sink: Correct/Incorrect?

55. Rules for Using DFD Symbols
Data Flow That Connects
YES NO
A process to another process
A process to an external entity
A process to a data store
An external entity to another external entity
An external entity to a data store
A data store to another data store

56. List the errors of this DFD

57. Example Employee Accounts Department Payroll Processing Employee File
Employee Data
Salary Statement
Accounts
Department
Payroll
Processing
Employee File
Updated
Data

58. What DFDs Do Not Do DFDs do not handle sequence
There is no notion of time in a DFD. It cannot be inferred that process 2 always follows process 1.
In many instances DFDs are drawn by considering a sequence of actions but that still does not mean that we can infer sequentially from a DFD.
DFDs do not handle priorities
In a situation where two processes want to read from the same file at the same time, which one wins? DFDs do not address the problem.
DFDs do not define the structure of the data
The structure of the data in the data stores is glossed over in DFDs and any structure of the data in data flows is similarly ignored in DFDs. The structure of the data is left to the data view of the system.

59. Context Diagram Top-level view of IS
Shows the system boundaries, external entities that interact with the system, and major information flows between entities and the system.
Example: Order system that a company uses to enter orders and apply payments against a customer’s balance

60. Context Diagram of Order System

61. Level-0 DFD
Shows the system’s major processes, data flows, and data stores at a high level of abstraction
When the Context Diagram is expanded into DFD level-0, all the connections that flow into and out of process 0 needs to be retained.

62. Context Diagram of Order System

63. Level-0 DFD of Order System

64. Lower-Level Diagrams Functional Decomposition Balancing
An iterative process of breaking a system description down into finer and finer detail
Uses a series of increasingly detailed DFDs to describe an IS
Balancing
The conservation of inputs and outputs to a data flow process when that process is decomposed to a lower level
Ensures that the input and output data flows of the parent DFD are maintained on the child DFD

65. Strategies for Developing DFDs
Top-down strategy
Create the high-level diagrams (Context Diagram), then low-level diagrams (Level-0 diagram), and so on
Bottom-up strategy
Create the low-level diagrams, then higher-level diagrams

66. Exercise:
Precision Tools sells a line of high-quality woodworking tools. When customers place orders on the company’s Web site, the system checks to see if the items are in stock, issues a status message to the customer, and generates a shipping order to the warehouse, which fills the order. When the order is shipped, the customer is billed. The system also produces various reports.
Draw a context diagram for the order system
Draw DFD diagram 0 for the order system

67. Identify Entities,Process,Data Stores & Data Flow
Customer
Warehouse
Accounting
Processes
1.0 Check Status
2.0 Issue Status Messages
3.0 Generate Shipping Order
4.0 Manage Accounts Receivable
5.0 Produce Reports
Data Stores
D1 Pending Orders
D2 Accounts Receivable
Data Flows
Order
In-Stock Request
Order Data
Status Data
Status Message
Shipping Order
Invoice
Shipping Confirmation
Payment
Accounting Data
Accounts Receivable Data
Inventory Reports
1.0
2.0
3.0
4.0
5.0

68. Context Diagram of Order System

69. Level-0 of Order System

70. Entity-Relationship (E-R) Diagram
A detailed, logical representation of the entities, associations and data elements for an organization or business.
Entity relationship diagramming is a technique that is widely used in the world of business and information technology to show how information is, or should be, stored and used within a business system.
The success of any organization relies on the efficient flow and processing of information.

71. Entity Relationship Diagram Notations
An entity is an object or concept about which you want to store information.

72. Attributes
Attributes are the properties or characteristics of an entity.
Attribute

73. Key attribute
A key attribute is the unique, distinguishing characteristic of the entity.
For example, an employee's social security number might be the employee's key attribute.

74. Relationships
Relationships illustrate how two entities share information in the database structure.

75. Cardinality
Cardinality specifies how many instances of an entity relate to one instance of another entity.
Ordinality is also closely linked to cardinality. While cardinality specifies the occurrences of a relationship, ordinality describes the relationship as either mandatory or optional.
In other words, cardinality specifies the maximum number of relationships and ordinality specifies the absolute minimum number of relationships. When the minimum number is zero, the relationship is usually called optional and when the minimum number is one or more, the relationship is usually called mandatory.

76. An E-R Diagram

77. Recursive relationship
In some cases, entities can be self-linked. For example, employees can supervise other employees.

78. Multivalued attribute
A multivalued attribute can have more than one value. For example, an employee entity can have multiple skill values.

79. Derived attribute
A derived attribute is based on another attribute. For example, an employee's monthly salary is based on the employee's annual salary.

80. Example relationships of different degrees

81. System Flowchart
A system flowchart explains how a system works using a diagram. The diagram shows the flow of data through a system.

82. Different shaped symbols are used....

83. The symbols are linked with directed lines (lines with arrows) showing the flow of data through the system.

84. An example of a system flowchart is shown below...