问题
填空题
在连接运算中,______连接是去掉重复属性的等值连接。
答案
参考答案:自然
解析: 本题考查关系基本运算中的连接运算。在连接运算中,按照字段值对应相等为条件进行的连接操作称为等值联接。而自然联接是去掉重复属性的等值联接。
在连接运算中,______连接是去掉重复属性的等值连接。
参考答案:自然
解析: 本题考查关系基本运算中的连接运算。在连接运算中,按照字段值对应相等为条件进行的连接操作称为等值联接。而自然联接是去掉重复属性的等值联接。
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