题目内容 (请给出正确答案)
提问人:网友c********1 发布时间:2022年3月24日 23:10
[单项选择题]

设F是属性组U上的一组函数依赖,下列叙述正确的是

A.若Y

X,则X→Y为F所逻辑蕴含

B.若X

U,则X→Y为F所逻辑蕴含

C.若X→Y为F所逻辑蕴含,且Z

U,则X→YZ为F所逻辑蕴含

D.若X→Y及Y→2为F所逻辑蕴含,则X→Z为F所逻辑蕴含

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