[SQL ] 正規化問題
請問主鍵的判斷方式是如何呢??
有一關聯R(A,B,C,D,E,F),其中
AB→C, ABC→D, ABC→E, ABC→F
明顯可以看出ABC才可決定所有屬性,但C可透過AB決定
所以主鍵是AB,請問這樣的觀念是正確的嗎?
另外...此關聯是第幾正規化呢?
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09/15 17:20, , 1F
09/15 17:20, 1F
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09/17 17:44, , 2F
09/17 17:44, 2F
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09/17 17:45, , 3F
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09/17 17:55, 8F