Can anyone elaborate about the 1st, 2nd and 3rd normalization forms? I know that the dependency is reduced by greater amount when we move from 1st to third but I'm confused about the mechanism applied in each form.

Question

anonymous · Answer

1st normal: first identify repeating fields and group them
 another table

2nd normal: it should be in 1st normal form and identify 
that all fields all dependent on primary key.

3rd normal: it should be in 2nd normal form and  check all 
fields all independent of other non-key attribute

Basically
1NF-No repeating elements or groups of elements
2NF-No partial dependencies on a concatenated key
3NF-No dependencies on non-key attributes

2NF covers the case of multi-column primary keys. 3NF is meant to cover single column keys. Simply stated, pull out columns that don’t directly relate to the subject of the row (the primary key), and put them in their own table.