Define Problems and Constraints
The designer has both formal and informal sources of information. If the company has existed for any length of time, it already has a system in place (either manual or computer-based). How does the existing system function? What input does the system require? What documents does the system generate? By whom and how is the system output used? studying the paper trail can be very informative. In addition to the official version of the system s operation, there is also the more informal, perhaps more real version; the designer must be shrewd enough to see how these differ.
Define Objectives
The DB designer must begin to address the following questions:
• What is the proposed system s initial objective?
• Will the system interface with other existing or future systems in the company?
• Will the system share the data with other systems or users?
Define Scope and Boundaries
Scope defines the extent of the design according to operational requirements.
Boundaries are imposed by existing hardware and software, the designer can choose the hardware and software that will best accomplish the system goal.
2- Database design
As you examine the procedures required to complete the design phase in the DBLC, remember these points:
• The process of database design is loosely related to the analysis and design of a larger system. The data com¬ponent is only one element of a larger information system.
• The systems analysts or systems programmers are in charge of designing the other system components. Their activities create the procedures that will help transform the data within the database into useful information.
• The database design does not constitute a sequential process. Rather, it is an iterative process that provides continuous feedback designed to trace previous steps.
The following figure explain Database design process
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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