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Consider the following dependencies and the BOOK table in a relational database design. Determine the normal form of the given relation.

ISBN $\rightarrow$ Title

ISBN $\rightarrow$ Publisher

Publisher $\rightarrow$ Address

  1. First Normal Form
  2. Second Normal Form
  3. Third Normal Form
  4. BCNF
in Databases by Boss (30.9k points) | 2.5k views

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The relation is in second normal form .

We first need to find Candidate key by taking closure of attributes = ISBN

Now with ER modelling we get relation in 1 NF .

for 2nf , we shouldnt have any partial dependency ( A non key shouldnt be fully functionally dependent on a subset of Ck )

Since our Ck is 1 attribute only we wont have that partial dependency

But now for 3nf , if you see we have Address which is transitively dependent on ISBN . Hence Transitive dependency exists .

So relation is in 2nf and not in 3nf
by Loyal (9.9k points)
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A non key shouldnt be fully functionally dependent on a subset of Ck 

It must be "PROPER subset". But what's the significance of "fully" here?

Fully functionally dependent mean it shouldnt have any redundant attribute
Yes and Proper subset is MUST .

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