NORMALIZATION
Is a process for evaluating and correcting table structures to minimize data redundancies, thereby reducing the likelihood of data anomalies.
Normalization works through a series of stages called normal forms. The first three stages are described as first normal form (1NF), second normal form (2NF) and third normal form (3NF).
From a structural point of view, 2NF is better than 1NF and 3NF is better than 2NF.
Denormalization
Produces a lower normal form, that is a 3NF will be converted to a 2NF through
denormalization
A successful design must also consider end-user demand for fast performance. Therefore you will occasionally be expected to denormalize some portions of database design in order to meet performance requirements
THE NEED FOR NORMALIZATION
In following example
We see in that example the structure of data set does not conform to the requirements of table nor does it handle data very well.
Consider the following deficiencies:
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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