- A.一个非主属性和四个主属性
- B.两个非主属性和三个主属性
- C.三个非主属性和两个主属性
- D.四个非主属性和一个主属性
正确答案及解析
正确答案
解析
此题考查数据库知识。由题干知：AC推出B，B又能推出DE，因此AC是唯一的候选键，其中AC分别是主属性，B、D、E为非主属性。
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