Latest Tutorials| Questions and Answers|Ask Questions?|Site Map



Home Answers Viewqa SQL What are different normalization forms?

Have Programming Question? Ask it here!
 
 
 


hemant kumar
What are different normalization forms?
1 Answer(s)      3 years and 9 months ago
Posted in : SQL


What are different normalization forms?


Advertisement
View Answers

November 18, 2010 at 4:57 PM


Hi,

1NF: Eliminate Repeating Groups- Make a separate table for each set of related attributes, and give each table a primary key. Each field contains at most one value from its attribute domain.

2NF: Eliminate Redundant Data- If an attribute depends on only part of a multi-valued key, remove it to a separate table.

3NF: Eliminate Columns Not Dependent On Key- If attributes do not contribute to a description of the key, remove them to a separate table. All attributes must be directly dependent on the primary key

BCNF: Boyce-Codd Normal Form- If there are non-trivial dependencies between candidate key attributes, separate them out into distinct tables.

4NF: Isolate Independent Multiple Relationships- No table may contain two or more 1:n or n:m relationships that are not directly related.

5NF: Isolate Semantically Related Multiple Relationships There may be practical constrains on information that justify separating logically related many-to-many relationships.

Thanks,



Related Tutorials/Questions & Answers:
Advertisements
Advertisements
 

 

 

DMCA.com