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First Normal Form

 
Sameer Jamal
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I am little bit confused about the first normal form well lets see what is the definition

According to Microsoft website

http://support.microsoft.com/default.aspx?scid=kb;en-us;283878
First Normal Form
� Eliminate repeating groups in individual tables.
� Create a separate table for each set of related data.
� Identify each set of related data with a primary key.

According to Databsae journal
http://www.databasejournal.com/sqletc/article.php/26861_1474411_4

� there are no repeating groups
� all the key attributes are defined
� all attributes are dependent on the primary key

Now suppose there is some data


So according to microsoft's definition the database will be in first normal form if we have following tables






Remember Create a separate table for each set of related data.
Identify each set of related data with a primary key.


But according to Databse journal's definition a database will be in First normal form if we have following single table.



Please clear me which is the first normal form.
[ February 22, 2006: Message edited by: Sameer Jamal ]
 
luceene works
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The Definition of 1NF says
"A relation is said to be in First Normal Form (1NF) if and only if each attribute of the relation is atomic. More simply, to be in 1NF, each column must contain only a single value and each row must contain the same columns."

Hence there are no related set and in 1NF we don't split data into separate tables to remove data redunducy.

So the description given in the database journal is correct.

Cheers
 
Jeff Albertson
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What, Microsoft is wrong?!
 
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