I am stuck up in Normalization. I have normalized till 3NF. However I do not how to perform BCNF. The 3NF table list are shown below.
Armstrong's Axiom:
Axiom of augmentation : If X->Y, then XZ->YZ for any Z
So,this can be applied to table 4,
IN Table 4,FD: {A, D, H, I} -> J. can be written as FD: {A, D, H, I,K} -> {J,K}
Then,we can apply decomposition axiom,
Decomposition : If X -> YZ then X -> Y and X -> Z
So,applying to table4,we get,
FD : {A, D, H, I,K} -> J,
FD : {A, D, H, I,K} -> K
so,the two FDs of table4 are:
FD : {A, D, H, I} -> J,
FD : {A, D, H, I,K} -> {J,K}
Thus {A,D,H,I,K} is a Super key ,by definition of BCNF ,we get table4 is in BCNF
Hope this helps.
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