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Relation R: [A,B,C,D,E,F] FD1: (A,B) - C,F FD2: (C,D) - E FD3: (D,E) - B

Is (x,y) the candidate key here? if not, what is?

philipxy
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Ryan Murphy
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    Well, no. A candidate key is here is some combination of A, B, C, D, E, and F. There might be more than one candidate key. – Mike Sherrill 'Cat Recall' Nov 13 '19 at 21:18
  • Re "is this right": Show the steps of your work following your reference/textbook, with justification--you may find mistakes that make your question unnecessary & we don't know exactly what algorithm you are following & we want to check your work but not redo it & we need your choices when an algorithm allows them & otherwise we can't tell you where you went right or wrong & we don't want to rewrite your textbook. Please see [ask], hits googling 'stackexchange homework' & the voting arrow mouseover texts. PS Finding CKs is a faq. PS Your question doesn't make sense. What are x & y? – philipxy Nov 13 '19 at 22:21
  • What does "I have these FDs" mean? "These are all the FDs that hold"?--Not possible. "These are all the non-trivial FDs that hold"?--Not possible. "These are some FDs that hold"?--Question can't be answered. Find out what a *cover* is & what the exact conditions are to apply a particular definition/rule/algorithm. To determine CKs & NFs we must be given FDs that form a cover. Sometimes a minimal/irreducible cover. And the set of all attributes must given. [See this answer.](https://stackoverflow.com/a/53386492/3404097) – philipxy Nov 13 '19 at 22:24

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