题目内容：
在学生表中要查找所有年龄大于30岁姓王的男同学，应该采用的关系运算是（ ）
A．选择 B．投影
C．联接
D．自然联接
参考答案：
答案解析：
单选题：在学生表中要查找所有年龄大于30岁姓王的男同学，应该采用的关系运算是（ ）
- 题目分类：公共基础知识
- 题目类型：单选题
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B．投影
C．联接
D．自然联接
B．投影
C．联接
D．自然联接
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