BCNF question
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c2fungry Offline
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Post: #1
BCNF question
small question, does it matter which FD we decompose for BCNF? Also if we are given a bcnf question, is it safe to assume the given FDs are 3NF unless stated otherwise?
2015-08-12 02:37
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merajisi Offline
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Post: #2
RE: BCNF question
latter is correct. i do not understand the first question

(2015-08-12 02:37)c2fungry Wrote:  small question, does it matter which FD we decompose for BCNF? Also if we are given a bcnf question, is it safe to assume the given FDs are 3NF unless stated otherwise?
2015-08-12 05:21
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c2fungry Offline
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Post: #3
RE: BCNF question
I'll refer to the practice question for bcnf, we start with the FD: B->CD. To break up the schema into the relations R1{B,C,D,A,G} and R2{B,E,F,H}.

What I'm trying to ask is that does it matter if we use a different FD? For example, could I use the FD, BF->H to find a different answer that still abides to being BCNF or did we choose B->CD for a specific reason?

(2015-08-12 05:21)merajisi Wrote:  latter is correct. i do not understand the first question

(2015-08-12 02:37)c2fungry Wrote:  small question, does it matter which FD we decompose for BCNF? Also if we are given a bcnf question, is it safe to assume the given FDs are 3NF unless stated otherwise?
2015-08-12 11:45
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merajisi Offline
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Post: #4
RE: BCNF question
Yes you can use a different FD

(2015-08-12 11:45)c2fungry Wrote:  I'll refer to the practice question for bcnf, we start with the FD: B->CD. To break up the schema into the relations R1{B,C,D,A,G} and R2{B,E,F,H}.

What I'm trying to ask is that does it matter if we use a different FD? For example, could I use the FD, BF->H to find a different answer that still abides to being BCNF or did we choose B->CD for a specific reason?

(2015-08-12 05:21)merajisi Wrote:  latter is correct. i do not understand the first question

(2015-08-12 02:37)c2fungry Wrote:  small question, does it matter which FD we decompose for BCNF? Also if we are given a bcnf question, is it safe to assume the given FDs are 3NF unless stated otherwise?
2015-08-13 10:49
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