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Question

Please some one help me in this question

 

 

Comments

4?

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yes but is my explanation correct : 

BC is C.K. 

so here  BC->E & BCD->A satisfy BCNF

but A->F , F->G , C->D , A->G violets BCNF

For A->F : Table will be (A,F) {F will be deleted from A,B,C,D,E,F,G}

For F->G : Table will Be (F,G) {we already deleted F from  A,B,C,D,E,F,G now delete G also }

For C->D : Table will be {C,D} {D will be deleted from A,B,C,D,E,F,G}

Now Rest of attribute {A,B,C,E} will form one table. 

Here We archived lossless decomposition , but dependencies BCD->A & A->G lost .

Is my explanation correct?

 

 

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Yes. The 4 tables will be formed in the same way you described, but I think the dependency A-> G will be indirectly present, bcoz of A-> F and F-> G

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OK THANKS

Answer 1

yes 4 tables,

CD

BCE

FG

ABCF