COMPUTER APPLICATIONS
DATABASE MANAGEMENT SYSTEMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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First normal form
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Second normal form
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Third normal form
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Fourth normal form
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Detailed explanation-1: -Third normal form (3NF) A table is in 3NF if it is in 2NF and it contains no transitive dependencies; that is, a condition in which an attribute (non-primary-key) is dependent on another attribute (non-primary-key) that is not part of the primary key.
Detailed explanation-2: -A given relation is said to be in its third normal form when it’s in 2NF but has no transitive partial dependency. Meaning, when no transitive dependency exists for the attributes that are non-prime, then the relation can be said to be in 3NF.
Detailed explanation-3: -Example of Third Normal Form The functional dependency set can be defined as ID->NAME, ID->SUBJECT, ID->STATE, STATE->COUNTRY. If A->B and B->C are the two functional dependencies, then A->C is called the Transitive Dependency. For the above relation, ID->STATE, STATE->COUNTRY is true.