Chapter 6 Normalization

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What would it look like Below shows an instance of this revised schema. Question: How far could we go Below shows an ultimate, but useless, decomposition. Notice that they are no longer related. 8
What have we learned 1. Decomposition can serve as a useful tool that augments conceptual modeling by cutting out some of the redundancy. 2. The criteria of choosing the right decomposition is not straightforward, especially when we have to deal with a complicated relation, which is where such guidance is needed the most. Thus, we will develop various techniques in this part, based on the idea of functional dependency, that will guide us through to develop various normal forms. 9
Page 1 and 2: Chapter 6 Normalization Conceptual
Page 3 and 4: Remember this one Consider the foll
Page 5 and 6: Another abnormally Assume that we w
Page 7: Decomposition The solution to the a
Page 11 and 12: Technically, ... ..., a functional
Page 13 and 14: FD examples Given the following val
Page 15 and 16: What do we really want We notice th
Page 17 and 18: Key is a special FD Note that the k
Page 19 and 20: Identify the FDs... Consider the ta
Page 21 and 22: The bad guy Consider the following
Page 23 and 24: What is happening As a result, we h
Page 25 and 26: What does that mean Every RDB is in
Page 27 and 28: The BCNF A relation schema S = (R,
Page 29 and 30: BCNF states that if this is the cas
Page 31 and 32: 4. A relation instance that is in a
Page 33 and 34: 5. BCNF relations with more than on
Page 35 and 36: 3NF could be redundant We saw earli
Page 37 and 38: A plan Since there is no redundancy
Page 39 and 40: An example Consider the following s
Page 41 and 42: An example The decomposition of Has
Page 43 and 44: A bit too late ..., which we will o
Page 45 and 46: BCNF Decomposition Let S 0 = (R, F)
Page 47 and 48: Via 3NF If we settle for 3NF, it is

Chapter 6 Normalization

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