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Explain Database Normalization?



Posted By: Avi Date: 7 October 2009 02:16:03 AM
 Answer:

Database Normalization is a process to ensure that every non-key column in every table is directly dependent on the key, the whole key and nothing but the key and this process benefits in the form of reduced redundancies, fewer anomalies, and improved efficiencies.

There are two major goals of database normalization: eliminating redundant data (for example, storing the same data in more than one table) and ensuring data dependencies make sense (only storing related data in a table).

The inventor of the relational model, E.F. Codd, had also introduced the concept of normalization and defined a series of guidelines for ensuring that databases are normalized. These are referred to as normal forms.

As of now, following five normal forms are used for database normalization process:
1) First Normal Form (1NF)
2) Second Normal Form (2NF)
3) Third Normal Form (3NF)
4) Fourth Normal Form (4NF)
5) Boyce-Codd Normal Form (BCNF)



Posted By: eTechPlanet

Date: 7 October 2009 02:16:03 AM
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