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问题 单项选择题

SQL语言的GRANT和REVOKE语句主要用来维护数据库的( )。

A．安全性

B．完整性

C．可靠性

D．一致性

答案

参考答案：A

解析：GRANT 和 REVOKE 两个语句分别是授予权限和回收权限语句，具有对 SQL语言的安全控制功能。

单项选择题

在整个结构化方法的出发点和实施步骤中，十分强调用户的

A．需求调查

B．可行性分析

C．逻辑设计

D．系统实施
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单项选择题

In country after country, talk of nonsmoker’s right is in the air. While a majority of countries have taken little (51) no action yet, some 30 nations have introduced legislated steps to control smoking. Many laws have been introduced in other countries to (52) clear the air for nonsmokers, or to cut cigarette consumption.

Smoking is harmful (53) the health of people. World governments should conduct serious campaigns against it. (54) on cigarette advertisements, plus health warnings on packages and ban on public smoking in certain places, (55) as theaters, cinemas and restaurants, are the most popular tools used by nations in (56) of nonsmokers or in controlling smoking. But world attention is also focusing on another step (57) will make the smoker increasingly self-conscious and uncomfortable about his habit. Great efforts should be made to (58) young people especially of the dreadful consequences of taking up the habit. And cigarette price should be raised.

In the long run, (59) is no doubt that everybody would be much better-off if smoking were banned altogether but many people are not (60) for such drastic action.

58().

A.encourage 

B.inform 

C.indicate 

D.illustrate
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