NormalizationPart 2

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NormalizationPart 2
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First Normal FormExample from Serverwatch.com

• No multi-valued attributes, no repeating groups
• Example of multi-valued attribute
• ?? How to query for students taking 3900 only

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First Normal Form

• No multi-valued attributes, no repeating groups
• Example of repeating group
• ?? How to query for students taking only 3900

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Correct First Normal Form
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Second Normal Form

• All non-key fields must be dependent upon the
  entire primary key.
• ??What are the dependency problems?

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Second Normal Form Correct

• Split into 3 tables based on dependencies

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Third Normal Form

• Prohibits transitive dependenciesa field is
  dependent on a non-key field

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Third Normal Form Correct
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Normalization Problem

• Sample Employee Records

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Table P5.11 Sample EMPLOYEE Records
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Figure P5.11 The Dependency Diagram for Problem
11 as Table Currently Appears
No 2nd Normal Form Problemswhy?
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Dependency Diagram Corrected
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CHEN ERD
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Comparison of ERD and Functional Dependency
Diagram