database - Does this qualify as a partial dependency? -

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With the non-prime attribute, the proper set of candidate key determines non-prime, whether it is partial dependency or 2 in NF ?

Kind of {AB} then BD -> C

Thus you are partial Define Dependency: For example, you have a relation R with column a. B C. D .

Based on the functional reliability defined by the business, the AB has been designated as the primary key (the candidate key) and the B -> D FD is present.

In that case, though AB is PK; But the non-key column D is specifically identified only by the B (part of the key combination) and not the whole key structure AB .

Then, D here is partly dependent on the main column and thus holding partial functional dependency which is 2NF Is against.

In your case, CK AB is not specifically identifying all areas; C is partly based on b ; In addition, C is based on non-key column D .

Therefore, it has PFD (partial functional dependency) and definitely not in 2 NF.


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