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Question

Comments

yes intrasitive means not transitive , I too think so.

3)"A prime attribute can transitively dependent on key of BCNF"

R(A,B,C,D) With ABC-> D , D-> A

what is key here (ABC),(DBC), So, this should be true

It will be true if "A prime attribute must transitively dependent on key of BCNF"

or

"A prime attribute can transitively dependent on nonkey of BCNF"

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4)"A prime attribute can intransitively dependent on key in 3NF relation"

R(A,B,C,D) With AB-> C

here C is prime attribute, which intransitively dependent on key.

if atleast one example satisfies, we can say

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tell me where am I wrong?

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Srestha.. In your example how C becomes prime attribute and AB is key.?? . I think another counter example would be good

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ok

AB->C, BD->A

now correct?

Answer 1

statement 1 and 2 both are true

Comments

your (2) example will be in 3 NF c.k=A,B,C

A->B

B->C

C->A

in L.h.s all of them is c.k so it will be in 3nf as well as BCNF .