Homework 2
ISE 382
Database Basics
15 points
Due Date – Friday Feb 3rd
•
Answer the following question from your textbook, page 95.
3.10, 3.12, 3.17, 3.18, 3.20
3.10 All functional dependencies document the fact that the knowledge of the
value of one or more attributes can be used to uniquely determine the value of
one or more associated attributes.
Functional dependencies may or may not be
based on a quantitative basis.
An example of a nonquantitative functional
dependency is FullName
HomeAddress.
This type of functional dependency
does not involve an equation.
Equations, however, can also form the basis of a
functional dependency, and can be translated into functional dependencies by
placing the independent variables (those whose values are free to change) in the
determinant attributes, and the dependent variable (the result of the calculation)
as the functionally determined attribute.
For example, the equation
(TotalBeforeTax * TaxRate) = Tax can be expressed as the functional
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 Spring '08
 KALE
 Relational model, Candidate key, Buyer Department

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