# Functional Dependency

1 vote
152 views
Consider a relation R(ABCD) with functional dependency F:{ AD → B, AB → C }. Is AB → C partial or total dependency?
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it is a transitive dependency Since here candidate keys AD.

AD->C , Here C is a non-prime attribute determined by combination of prime attribute and Non-prime attribute and here it is a transitive dependecny.
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Yes, it is a transitive dependency.
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https://gateoverflow.in/492/gate2008-69

its transitive dependency

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0
No partial dependency, no transitive dependency

will be in 3NF
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ma'am see my comment,it is right?
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@Lakshman Patel RJIT Bro check out the link posted by @Soumya29

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Navathe says

from key itself remove an attribute and still if there dependency exists then it will be partial dependency

Here that is not the case

So, no partial dependency

Now A->B->C

here if B is not key or not part of key and then onlytransitive dependency exists

But here AB->C

B is part of key

So, can we not say no transitive dependency too?
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@srestha ma'am

According to a similar question in ACE material, AB is considered to be a part of key.

## Related questions

1
270 views
Consider a relation $R\left ( A,B,C,D,E \right )$ and functional dependencies are $F=\left \{ AC\rightarrow B,C\rightarrow D,A\rightarrow E,C\rightarrow B \right \}$ Relation $R$ is decomposed into $R_{1}\left ( A,B,C \right )$ and $R_{2}\left ( C,D \right )$ Then Is it a lossless decomposition? I am getting doubt, how it can be not lossless decomposition?
Can someone explain the paragraph marked based on relation $r$ given in Figure 7.2? Reference: Database System Concepts by Silberschatz, Korth, Sudarshan 4th Edition. ​​​​​