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BCNF doubt [closed]

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If a relation R is 3 NF and atmost one compound candidate key [remaining candidate keys are simple ]

then R is :-

A:-also in BCNF

B:-not BCNF

C:-may not BCNF

D:-none
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what does Y-X mean there ?

does it mean set difference  of X & Y ?

Also can you please tell what is simple candidate key and compound candidate key?

0

does it mean set difference  of X & Y ?

yes.

 

what is simple candidate key and compound candidate key

simple candidate key means, the key have only one attribute

compound candidate key means, the key have more than one attribute

if AB combinely forms the key then it is compound candidate key

 

read my answer, it will clear your doubts

0
thanks a lot for the explanation..

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