For relation where primary key contains multiple attributes, no non-key attribute should be functionally dependent on a part of 

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问题 For relation where primary key contains multiple attributes, no non-key attribute should be functionally dependent on a part of primary key. This relation R is at least in(66).

选项 A、3NF
B、2NF
C、INF
D、BCNF

答案A

解析 译文:对于主键包含多个属性的关系,没有非主属性函数依赖于部分主键。这样的关系R至少是3NF。
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