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问题 单项选择题

在一个数据库中，模式与内模式的映像个数是( )。

A) 1个
B) 与用户个数相同
C) 由设置的系统参数决定
D) 任意多个

答案

参考答案：A

解析： 一个数据库只有一个模式，也只有一个内模式，所以模式和内模式映像是惟一的。它定义了数据库全局逻辑结构与存储结构之间的对应关系。模式和内模式映像保证了数据与程序的物理独立性。

改错题

.

第II卷

第四部分  写作（共两节，满分35分）

短文改错（共10小题；每小题1分，满分10分）

此题要求改正所给短文中的错误。短文中有10处错误，每句最多有两处。错误设计一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在此符号下面写出该加的词。

删除：把多余的词用斜线（﹨）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1、每处错误及修改均仅限一词。

2、只允许修改10处，多者（从第11处起）不计分。

Welcome to our English Corner. It set up about four years before. Since then on many high school students have joined in it. The students from different schools gather round on Sunday mornings, and there are also some college students or foreigners. We talked about everything we know and show interest in. We also exchange our effective method in English learning. We think we have learned much here.

The English Corner is a really addition to our English class and popular with students. Parents and teachers appreciate them very much because they all believe it is of great help to their children. If you want to know much about it, you may talk to students here.
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多项选择题

中医鼻科常用的辨证方法有

A．八纲辨证

B．六经辨证

C．卫气营血辨证

D．脏腑辨证

E．气血津液辨证
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