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tuse 22 Junior Poster

Hi,

I was reading the book "Fundamentals of Database Systems" by Elmasri and Navathe. In that it is given that for a relation to be in 2nd NF, every non prime attribute (attribute which is not a part of any candidate key) should be fully functionally dependent on any candidate key.

Also a relation is given as

EMP_DEPT(ENAME,SSN,BDATE,ADDRESS,DNUMBER,DNAME)

where,
EMP_DEPT- Employee Department
ENAME- Employee Name
SSN-Social Security Number
BDATE-Birthdate
DNUMBER- Dept Number
DNAME- Dept Name

This is said to be in 2NF.

However if you see the DNAME attribute which is non prime (not a part of candidate key), it is not functionally dependent on any candidate key (SSN in this case).

So is it correct that the relation is in 2NF or is there something that I have missed?

Thanks

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