prime attribute
an attribute of a relation schema 
is called a prime attribute of if it is a member of some candidate key of . an attribute is called a nonprime if it is not a prime attribute--that is, if it is not a member of any candidate key.
[cite:;from @elmasri_db_2015 chapter 14.3 normal forms based on primary keys]
is called a prime attribute of if it is a member of some candidate key of . an attribute is called a nonprime if it is not a prime attribute--that is, if it is not a member of any candidate key.
[cite:;from @elmasri_db_2015 chapter 14.3 normal forms based on primary keys]