Databases II INF3703 SUMMARY

whole known as an Information System, which provides for data collection, storage, transformation, and retrieval. Systems analysis is the process that establishes the need for an information system and its extent. The process of creating an information system is known as systems development. The performance of an information system depends on three factors: 1. Database design and implementation 2. Application design and implementation 3. Administrative procedures The term database development describes the process of database design and implementation. The primary objective in database design is to create completer, normalized, nonredundant and fully integrated conceptual, logical and physical models. 9-2 The Systems Development Life Cycle (SDLC) [p.442] The SDLC traces the history of an information system. 9-2a Planning [p.442] An initial assessment of the information flow and extend requirement must be made during this discovery portion of the SDLC. Such an assessment should answer some important questions: - Should the existing system be continued? If the information generator does its job well, there is no point in modifying or replacing it. - Should the existing system be modified? If the initial assessment indicates deficiencies in the extent and flow of the information, minor( or major) modification might be needed. - Should the existing system be replaced? The initial assessment might indicate that the current system’s flaws are beyond fixing. The feasibility study must address the following: - The technical aspects of hardware and software requirements - The decision might not yet be vendor-specific, but must address the nature of the hardware requirements and the software requirements. - The system cost - The admittedly mundane question “can we afford it?” is crucial. The answer might force a careful review of the initial assessment. At some point, the decision may be between building a system “in house” or buying a 3rd party vendor system. - The operational Cost - Does the company possess the human, technical and finan