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}。 （请作答此空）为关系R的候选关键字。分解（ ）是无损连接，并保持函数依赖的。
- A.AB
- B.DE
- C.CE
- D.DB
正确答案及解析
正确答案
解析
根据无损连接的判定算法，对选项A构造初始的判定表如下
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