A table is in 1NF if there and no duplicate rows in the table. Each cell is single-valued.
A table is in 2NF if it is in 1NF and if all non-key attributes are dependent on all of the key. A table is in 2NF if it is in 1NF and if it has no partial dependencies
A table is in 3NF if it is in 2NF and if it has no transitive dependencies
A table is in BCNF if it is in 3NF and if every determinant is a candiate key.
A table is in 4NF if it is in BCNF and it it has no multi-valued dependencies.
A table is in 5NF if it is in 4NF and it has no join dependency.
Superkey,Candidate key,Primary key
A superkey is any set of attributes such that the values of the attributes(taken together)uniquely identify one entity in the entity set.
A candidate key is a minimal superkey.
A primary key is one of the candidate keys, designated by the Database designer.
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