Concept explainers
Normalization:
The process used to minimize data redundancy and dependency in a relational
Second normal form (2NF):
- The value of all non-primary key attributes should be dependent on the primary key attribute.
- If any attribute is depending on the partial primary key then it should determine the other attributes for an instance of the entity.
- The partial dependencies should be removed from the data model.
Third normal form (3NF):
- The value of any non-primary key attributes will not depend on any other non-primary key attributes.
- If any non-primary key attributes depend on any other non-primary key attribute then it should be moved or deleted.
- It is termed as transitive dependency.
Partial dependency:
A partial dependency exists at that time of an attributes depends only a part of primary key. This dependency is related with 1st normal form.
Transitive dependency:
A transitive dependency exists at that time of an attributes depends on another attribute which is not part of primary key.
Functional dependency:
An association between two attributes or two set of attributes in a same relational database table, which is having some constraints is known as functional dependency.
- In a table one attribute is functionally dependent on another attribute to take one value.
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Chapter 6 Solutions
Database Systems: Design, Implementation, & Management
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