对关系S和R进行集合运算，结果中既包含S中的所有元组也包含R中的所有元组，这样的集合运算称为（　　）。 -题库考试答案搜索网

对关系S和R进行集合运算，结果中既包含S中的所有元组也包含R中的所有元组，这样的集合运算称为（　　）。

单选题

2021-07-17 21:15

A、并运算
B、交运算
C、差运算
D、积运算

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正确答案

A

试题解析

标签：综合类计算机计算机二级网络技术数据库技术信息安全技术嵌入式系统开发技术网络工程师数据库工程师信息安全工程师嵌入式系统开发工程师 2013年全国计算机等级考试二级JAVA上机模拟试卷(7)

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