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company, had to be part of the primary key of the table. This would be handled very
simply and naturally with a functional dependency that looks like this:
Book Number, Customer Number, Date, Price
Quantity
.
The complete list of functional dependencies is shown in Figure 7.37. First
normal form for the Good Reading Bookstores example would consist of the list of
its attributes with the following attributes in the primary key:
Publisher Name
Author Number
Book Number
Customer Number
Date.
Moving from first to second normal form, including incorporating the rule
described above for the many-to-many relationship with no intersection data, would
directly yield the tables of Figure 7.21. As there are no instances of a non-key
attribute defining another non-key attribute, this arrangement is already in third
normal form.
Publisher Name
City
Publisher Name
Country
Publisher Name
Telephone
Publisher Name
Year Founded
Author Number
Author Name
Author Number
Year Born
Author Number
Year Died
Book Number
Book Name
Book Number
Publication Year
Book Number
Pages
Book Number
Publisher Name
Customer Number
Customer Name
Customer Number
Street
Customer Number
City
Customer Number
State
Customer Number
Country
Book Number, Author Number
null
(or)
Book Number
Author Number
Author Number
Book Number
F IGURE 7.37
List of defining associations (functional
dependencies) for the attributes of the
Good Reading Bookstores example
Book Number, Customer Number, Date,
Quantity
Book Number, Customer Number, Date
Price
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