9. 属于传统的集合运算的是（）。 - 查题网

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国家开放大学 / 数据库应用技术

9. 属于传统的集合运算的是（）。

A.
选择运算

B.
投影运算

C.
连接运算

D.
并运算

积分

数据库应用技术

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