[課業] 資料庫正規化問題
題目如下：
一個表格R(A,B,C,D,E),屬性間的功能相依為：
A→BC,
CD→E,
B→D,
E→A
請將此表格分割成符合BCNF的表格.
請問各位大大這題要如何分割？？
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◆ From: 42.70.62.189
推
02/15 18:46, , 1F
02/15 18:46, 1F
→
02/15 18:46, , 2F
02/15 18:46, 2F
→
02/15 18:48, , 3F
02/15 18:48, 3F
請問一下lancelot123大大,你的第一步驟將表格拆成R1(A,B,C,E)中的主鍵還是A嗎?
那原本要CD才能決定的E，現在是誰會決定E?
推
02/15 18:59, , 4F
02/15 18:59, 4F
推
02/15 19:04, , 5F
02/15 19:04, 5F
請問canatmis大大，你的答案是怎麼推出來的??可以稍微說明一下嗎?謝謝^^
※ 編輯: tobywu1202 來自: 42.70.62.189 (02/15 23:27)
※ 編輯: tobywu1202 來自: 42.70.62.189 (02/15 23:30)
→
02/16 00:54, , 6F
02/16 00:54, 6F
→
02/16 00:54, , 7F
02/16 00:54, 7F
→
02/16 00:55, , 8F
02/16 00:55, 8F
→
02/16 00:57, , 9F
02/16 00:57, 9F
推
02/16 14:49, , 10F
02/16 14:49, 10F
→
02/16 14:51, , 11F
02/16 14:51, 11F
→
02/16 14:52, , 12F
02/16 14:52, 12F
→
02/16 14:54, , 13F
02/16 14:54, 13F
→
02/16 14:55, , 14F
02/16 14:55, 14F
→
02/16 14:55, , 15F
02/16 14:55, 15F
→
02/16 14:57, , 16F
02/16 14:57, 16F
→
02/16 14:58, , 17F
02/16 14:58, 17F
→
02/16 15:00, , 18F
02/16 15:00, 18F
推
02/16 15:16, , 19F
02/16 15:16, 19F
推
02/17 18:25, , 20F
02/17 18:25, 20F
→
02/17 18:26, , 21F
02/17 18:26, 21F
→
02/17 18:27, , 22F
02/17 18:27, 22F
→
02/17 18:28, , 23F
02/17 18:28, 23F
推
02/18 12:58, , 24F
02/18 12:58, 24F
→
02/18 13:00, , 25F
02/18 13:00, 25F
→
02/18 13:02, , 26F
02/18 13:02, 26F
→
02/18 13:04, , 27F
02/18 13:04, 27F
→
02/18 13:05, , 28F
02/18 13:05, 28F
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