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Summary
Database normalization is a process performed on your tables to make them less likely to fall prey to various common kinds of data anomaly:1st normal form contains no repeating groups and guarantees that all attributes are dependent on a primary key.2nd normal form contains no partial dependencies.3rd normal form contains no transitive dependencies.For practical purposes, 3rd normal form is usually sufficient; indeed, overnormalizing can lead to performance issues, with the database having to perform too many joins.Boyce-Codd normal form ensures each determinant is a candidate key.4th normal form contains no more than one multivalued dependency.5th normal form ensures tables cannot be reduced to smaller tables with different keys. Domain key normal form is a theoretical ideal beyond the scope of this book.
