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+2 votes
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in Databases by (165 points)
edited by | 127 views
+1

as per my knowledge,

in the FD CD -> E, D is not redundant....

why ?

due to CD -> E only, C -> D happens via E ->A  A -> B and B -> D.

 

what is the solution they provided?

0
Yes that's what I did wrong in this question.. I chose A as answer but answer is B
0

@Shaik Masthan @tusharforever @srestha I have a doubt here.

CD ---> E , D is extraneous attribute only if C closure can generate D on removal of D? 

I dont get this condition would you please elaborate?

0
i didn't get your doubt correctly
0

@Shaik Masthan

My doubt is why  in the FD CD -> E, D is not redundant....?

0
Then no comments
+1
Thanks alot I appreciate your time.!!

1 Answer

+1 vote
Answer is b because left side of each function dependencies  is unique.
by (75 points)
0

@Jony Bhatt

What do you mean by left side of each function is unique??

0
The condition for which you talking about "left side of each function dependencies  is unique", may be necessary but not sufficient.
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