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System development And Life Cycle-Analysis And Design

  • Analysis

Stage: Detailed evaluation of present system data collection.

Key Question: What must be done to solve the problem? what are the facts?

Result: Logical model of system. Ex: Data flow diagram, data dictionary.

• Analysis is a detailed study of various operations performed by a system and their relationships within and outside of the system.

• One aspect of it defining the boundaries of system and determining weather or not the system should consider other related system.

• Data is collected in available files during analysis.

• Interview is commonly used tool in analysis. It requires special skills and sensitivity to the subject.

• Training, experience and common sense are required for collecting needed information to do analysis.

• After analysis analyst has firm understanding of what is to be done.

  • Design

Stage: General design specification, detailed design specification, program construction and testing (output, input, files, procedures)

Key Question: In general, how must the problem to be solved? Specifically, how must the problem be solved ? What is the system flow? Does user approve the system?

Result: Design of alternative solutions, final cost analysis, hardware specifications, approval of system by user programs, actual hardware use, security, audit and operating.

• Describes final systems and refers to the technical specifications that will be applied in implementing the system and also includes construction of programs.

• First step➡️Determine how the output is produced and in what format.

• Second step➡️Input data and master files (data base) have to be designed to meet the requirements of proposed output. Also include list of program needed to be meet objectives of system.

• Final step➡️Details of estimation of impact of system on user and justification of system is documented and evaluated by management.

• Final report require procedural flowcharts, record and report layout and workable plan for implementing system and information on money, hardware, facilities and estimated cost.

• If analyst and programmer are separate analyst must perform certain functions while writting programs so the mistakes in designing can be prevented.

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