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To find the canonical cover of the given set of functional dependencies, we need to first simplify the given set of functional dependencies by removing redundant dependencies and then find the minimal cover. The steps to find the canonical cover are as follows:

Step 1: Remove redundant dependencies

We can see that the dependencies CF->BD and ACD->B are redundant because they can be inferred from the other dependencies. Hence, we can remove them.

The simplified set of functional dependencies is:

f1: AB -> C

f2: C -> A

f3: BC -> D

f4: BE -> C

f5: CE -> F

f6: D -> E

Step 2: Find the closure of each functional dependency

f1: AB+ = ABCDEF

f2: C+ = CADEFB

f3: BC+ = BCDEF

f4: BE+ = BECFAD

f5: CE+ = CEFAD

f6: D+ = DE

Step 3: Remove redundant dependencies using the Armstrong's axioms

We can use the Armstrong's axioms to check for redundant dependencies. The axioms are:

Reflexivity: If Y is a subset of X, then X -> Y.

Augmentation: If X -> Y, then XZ -> YZ for any Z.

Transitivity: If X -> Y and Y -> Z, then X -> Z.

Using these axioms, we can check for redundancy as follows:

f1: AB+ = ABCDEF

f1+: AB -> CDEF

f2: C+ = CADEFB

f2+: C -> ADEFB

f3: BC+ = BCDEF

f3+: BC -> DEF

f4: BE+ = BECFAD

f4+: BE -> CFAD

f5: CE+ = CEFAD

f5+: CE -> FAD

f6: D+ = DE

f6+: D -> E

Step 4: Find the minimal cover

We can remove redundant dependencies from the simplified set of functional dependencies using the Armstrong's axioms. The minimal cover is:

f1: AB -> C

f2: C -> A

f3: BC -> D

f4: BE -> C

f5: CE -> F

f6: D -> E

Therefore, the canonical cover of the given set of functional dependencies is:

AB -> C

C -> A

BC -> D

BE -> C

CE -> F

D -> E
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0 votes
CE -> A and CF-> B can be eliminated. C -> A makes CE -> A redundant. CF -> D makes CF -> B redundant.

C)+ contains A, so ACD -> B can be reduced to CD -> B.

Ans:

AB -> C

C -> A

BC -> D

CD -> B

BE -> C

CE -> F

CF -> D

D -> E
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