A Guide to SQL
9th Edition
ISBN: 9781111527273
Author: Philip J. Pratt
Publisher: Course Technology Ptr
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Chapter 2, Problem 9RQ
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Functional dependency:
- A column “X” is said to be functionally dependent on another column “Y”, when at any point of time, a value for “X” determines a single value for “Y”.
- In other words, a column “X” is said to be functionally dependent on another column “Y”, when two tuples agree on attribute “X” values then they should also agree on attribute “Y” values.
- It is usually represented as “XY”, where the terms “X” and “Y” are composite.
- It can be said as either “Y” is functionally dependent on “X” or as “X” functionally determines “Y”...
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Chapter 2 Solutions
A Guide to SQL
Ch. 2 - Prob. 1RQCh. 2 - What is an attribute?Ch. 2 - What is a relationship? What is a one-to-many...Ch. 2 - Prob. 4RQCh. 2 - What is a relation?Ch. 2 - Prob. 6RQCh. 2 - Prob. 7RQCh. 2 - How do you qualify the name of a field, and when...Ch. 2 - Prob. 9RQCh. 2 - What is a primary key? What is the primary key for...
Ch. 2 - Prob. 11RQCh. 2 - Prob. 12RQCh. 2 - Define second normal form. What types of problems...Ch. 2 - Define third normal form. What types of problems...Ch. 2 - Prob. 15RQCh. 2 - Prob. 16RQCh. 2 - List the changes you would need to make to your...Ch. 2 - Prob. 1TDCh. 2 - Prob. 2TDCh. 2 - Prob. 3TDCh. 2 - Prob. 4TDCh. 2 - Prob. 5TDCh. 2 - Prob. 1CATCh. 2 - Identify the functional dependencies in the...Ch. 2 - Prob. 3CATCh. 2 - Determine the functional dependencies that exist...Ch. 2 - Prob. 2SCGCh. 2 - Prob. 3SCG
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