试题与答案

在关系模式R(U)中,如果X→Y,Y→Z,且Y不是X的子集,不存在X←→Y的情况,则

题型:填空题

题目:

在关系模式R(U)中,如果X→Y,Y→Z,且Y不是X的子集,不存在X←→Y的情况,则称Z______依赖于X。

答案:

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