Can you list and explain the levels of database normalization?
sobes.tech AI
Answer from AI
Normalization levels are a set of rules for organizing data in a database to minimize redundancy and improve integrity.
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First Normal Form (1NF): All fields contain atomic (indivisible) values, with no repeating groups.
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Second Normal Form (2NF): 1NF is satisfied, and all non-key attributes depend fully on the entire composite key (if the key is composite).
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Third Normal Form (3NF): 2NF is satisfied, and there are no transitive dependencies between non-key attributes (non-key fields do not depend on each other).
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Boyce-Codd Normal Form (BCNF): A stricter version of 3NF, where every determinant is a key.
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Fourth Normal Form (4NF): Eliminates multivalued dependencies.
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Fifth Normal Form (5NF): Eliminates redundancy caused by joins.
In practice, normalization is most often applied up to 3NF or BCNF to balance performance and data integrity.