database normalization - BCNF decomposition that results in different decompositions (both faithful or faithless)? -
this question 19.10 (4) in textbook database management systems raghu ramakrishnan, johannes gehrke (in case anyone's curious - reply not included of course, why needed ask)
and noticed there 2 ways create bcnf decomposition:
we're given r = abcd , functional dependencies: -> b, b -> c, c -> d
key: can decompose bcnf either using b -> c or c -> d @ start
if decompose along b -> c @ start, r1 = ab , r2 = bc , r3 = bd (this not faithful) if decompose along c ->d @ start, r1 = ab, r2 = bc , r3 = cd (this faithful)
i'm quite new doing bcnf decomposition, correct? it's possible have multiple different bcnf decompositions depending on chosen starting fd?
thanks in advance :)
database-normalization bcnf
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