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下列不属于非平凡函数依赖的是______。
A) (CustomerID，ProviderID，BuyDate)→GoodsName
B) (CustomerID，ProviderID，BuyDate)→GoodsName，ProviderID
C) (CustomerID，ProviderID，BuyDare)→GoodsClassID
D) (CustomerID，ProvideIID，BuyDate)→ProviderID
A．
B．
C．
D．
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更多 “ 下列不属于非平凡函数依赖的是______。A) (CustomerID，ProviderID，BuyDate)→GoodsNameB) (CustomerID，ProviderID，BuyDate)→GoodsName，ProviderIDC) (CustomerID，ProviderID，BuyDare)→GoodsClassIDD) (CustomerID，ProvideIID，BuyDate)→ProviderIDA．B．C．D． ” 相关考题
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填空题如果X→Y（非平凡函数依赖，并且X不函数依赖于Y）、Y→Z，则称Z（）于X。
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