设关系模式R(U，F），其中R上的属性集U={A，B，C，D，E}，R上的函数依赖集F=｛A→B，DE→B，CB→E，E→A，B→D｝。（）为关系R的候选关键字。
- A.A
- B.DE
- C.CE
- D.DB
正确答案及解析
正确答案
解析
本题考察求解关键字
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