- A.只有一个候选关键字AC
- B.只有一个候选关键字AB
- C.有两个候选关键字ACBC
- D.有两个候选关键字AC.AB
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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