Normalization Review

1
Normalization Review

• MIS 372
• Database Management
• Shaun Simpson
• WSU Vancouver

2
Normalization

• First Normal Form - Eliminating Repeating Groups
• Second Normal Form - Eliminating Partial
  Dependencies
• Third Normal Form - Eliminating Transitive
  Dependencies
• Boyce-Codd Normal Form - Eliminating Nonkey
  Determinants

3
Normalization

• Fourth Normal Form - Eliminating Multivalued
  Dependencies
• Beyond Fourth Normal Form - The Voyage to Utopia
• Domain Key Normal Form - Another Road to Utopia
• A Suggested Process for Normalization
• Examples of the Normalization Process

4
Issues in the Practice of Designing Table
Structures

• Limitations of Normalization
• Treatment of Computed and Summary Data
• Capturing the Effects of Time
• Defining and Describing Attribute Domains
• Domain Restrictions
• Cross attribute Domain Restrictions

5
Data AnomaliesExamples
Addition
Deletion
Update
6
The Steps of Normalization
7
An Unnormalized Table
8
Another Unnormalized Table
9
First Normal Form
10
A Table with a Partial Dependency
11
Second Normal Form
12
A Table with Transitive Dependencies
13
Third Normal Form
14
A Table with a Nonkey Determinant
15
Boyce-Codd Normal Form
16
A Table with Multivalued Dependencies
17
Fourth Normal Form
18
A Proposed Normalization Process for Database
Designers
Examine each table of the proposed structure and
perform the following operations (1) Remove any
repeating groups of attributes (multivalued
attributes) to a separate table. If there are
independent sets of multivalued attributes, place
each set in a separate table. (2) Remove any
attributes that are functionally determined by
only a portion of a concatenated key to a
separate table. (3) Remove any attributes that
are functinally determined by a nonkey attribute
to a separate table. (4) Repeat steps 1-3 for any
new tables created.
19
THE KEY
All Atributes in every table must be determined
by the key, the whole key, and nothing but the
key.