DATABASE KEY
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Consider the relation R(A,B,C,D) with FDs AB -> C, C -> D, D ->A. What is the 3NF status of R. 1. R is in BCNF already. 2. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, and R2(B,D,F) with FDs B -> D, D -> F. 3. R is not in BCNF. It must be divided into R1(C,E) with FDs C -> E, R2(D,F) with FDs D -> F and R3(A,B). 4. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, R2(B,D,F) with FDs B -> D, D -> F, and R
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Consider the relation R(A,B,C,D) with FDs AB -> C, C -> D, D ->A. What is the 3NF status of R. 1. R is in BCNF already. 2. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, and R2(B,D,F) with FDs B -> D, D -> F. 3. R is not in BCNF. It must be divided into R1(C,E) with FDs C -> E, R2(D,F) with FDs D -> F and R3(A,B). 4. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, R2(B,D,F) with FDs B -> D, D -> F, and R
We are more than willing to help those that are stuck: but that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for us to do it all for you. So we need you to do the work, and we will help you when you get stuck. That doesn't mean we will give you a step by step solution you can hand in! Start by explaining where you are at the moment, and what the next step in the process is. Then tell us what you have tried to get that next step working, and what happened when you did. Consider this: just posting your homework question and hoping somebody will give you the answer so you can just tick a multiple choice box is futile. You have no idea if the answer you're given is right or wildly wrong ... and unless you actually learn this stuff you will have no idea at all!
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony "Common sense is so rare these days, it should be classified as a super power" - Random T-shirt AntiTwitter: @DalekDave is now a follower!
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Consider the relation R(A,B,C,D) with FDs AB -> C, C -> D, D ->A. What is the 3NF status of R. 1. R is in BCNF already. 2. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, and R2(B,D,F) with FDs B -> D, D -> F. 3. R is not in BCNF. It must be divided into R1(C,E) with FDs C -> E, R2(D,F) with FDs D -> F and R3(A,B). 4. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, R2(B,D,F) with FDs B -> D, D -> F, and R
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Consider the relation R(A,B,C,D) with FDs AB -> C, C -> D, D ->A. What is the 3NF status of R. 1. R is in BCNF already. 2. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, and R2(B,D,F) with FDs B -> D, D -> F. 3. R is not in BCNF. It must be divided into R1(C,E) with FDs C -> E, R2(D,F) with FDs D -> F and R3(A,B). 4. R is not in BCNF. It must be divided into R1(A,C,E) with FDs A -> C, C -> E, R2(B,D,F) with FDs B -> D, D -> F, and R
Now I feel sorry for missing this question. Normalization is one of the things you have to learn, and not just for databases. It will give you more insight into data. Let me stress that again, you want to master this, it is what makes a master. Can you give me a real life analogy for your abstract question? Otherwise, I'd just have to reply with the rules which you already know. And BCNF comes after 3NF; if it in 3NF, it not guaranteed to be BCNF, so answer one falls. Leaves you with three. Also, 3NF and BCNF rather close - if you can answer it, you master it.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
