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29 votes
29 votes
State True or False with reason

There is always a decomposition into Boyce-Codd normal form (BCNF) that is lossless and dependency preserving.
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4 Answers

Best answer
43 votes
43 votes
False
BCNF decomposition can always be lossless, but it may not be always possible to get a dependency preserving BCNF decomposition.
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7 votes
7 votes
bcnf decomposition guarantees lossless and d.p may not is correct one
1 votes
1 votes

false not every relation can decompose into BCNF with dependency preserving and lossless.

you can see here: relation R is not possible to decompose into BCNF with dependency preserving and lossless.

R(ABC)   F={AB->C , C->A } 

Answer:

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