Illustrates the third normal form

Question

Illustrates the third normal form?

Answer 1

An entity is in the third normal form when it is in the second normal form and all of its attributes are not transitively dependent upon the primary key. Transitive dependence implies that descriptor key attributes deepens not only on the entire primary key, but also upon other descriptor key attributes which, in turn, depend upon the primary key. In SQL terms, the third normal form implies that no column in a table is dependent upon a descriptor column which, in turn, depends upon the primary key.

Firstly for 3NF, the table should be in 2NF, plus, we wish for to ensure that the non-key fields are dependent on ONLY the PK, and not another non-key field for its existence. It is very same to 2NF, except that here you are comparing the non-key fields to OTHER non-key fields. Because, we know that the relationship to the PK is good, as we established that in 2NF.