问题
单项选择题
在数据库的三级模式结构中，内模式的个数
A．只有1个
B．与用户个数相同
C．由系统参数决定
D．有任意多个
答案
参考答案：A
解析：内模式跟模式是一一对应的关系，只能有一个模式和内模式。
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在数据库的三级模式结构中，内模式的个数
A．只有1个
B．与用户个数相同
C．由系统参数决定
D．有任意多个
参考答案：A
解析：内模式跟模式是一一对应的关系，只能有一个模式和内模式。
| 选词填空。(从方框中选出最恰当的10 个词用其恰当的形式填空，每词限用一次。) | |
She helps docters and patients (病人). Some people call her "Angle in White" (白衣天使). Peter's __4__ is a police officer (警官). His work is kind of dangerous. __5__ are afraid of him. Peter's aunt is a teacher. She __6__ in a middle school. She likes __7__. She thinks it's an __8__ job. Peter's parents are __9__. They work in a restaurant. They work __10__. They are very happy. |