题目内容

下列关于关系数据库中数据表的描述,正确的是( )。

A. 数据表相互之间存在联系,但用独立的文件名保存
B. 数据表相互之间存在联系,但用表名表示相互间的联系
C. 数据表相互之间不存在联系,完全独立
D. 数据表既相对独立,又相互联系

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