试题与答案

在关系模型中,把数据看成一个二维表,每一个二维表称为一个______。

题型:填空题

题目:

在关系模型中,把数据看成一个二维表,每一个二维表称为一个______。

答案:

参考答案:关系

解析: 在关系模型中,把数据看成_个二维表,每一个二维表称为一个关系。表中的每一列称为一个属性,相当于记录中的一个数据项,对属性的命名称为属性名;表中的一行称为一个元组,相当于记录值。

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题型:填空题

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7. How's it going? It's _________(很糟糕).

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