题目
题目
单项选择题

Which of the following is NOT true about Candidate keys?

选项
A.There can only ever be one Candidate Keys in a relation or table.
B.Each Candidate key must uniquely identify every row in the table.
C.A Candidate Key can be any column or a combination of columns that can qualify as unique key in a relation or table.
D.A Candidate key prevents duplicate rows and ensures consistency.
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标准答案
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思路分析
To analyze the statements about Candidate keys, I will evaluate each option on its own terms. Option 1: 'There can only ever be one Candidate Keys in a relation or table.' This claim is incorrect. In relational databases, a relation can have multiple candidate keys—the sets of attributes that could each uniquel......Login to view full explanation

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