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问题 单项选择题

在关系数据库中，为了简化用户的查询操作，而又不增加数据的存储空间，则应该创建数据库对象是

A．table(表)

B．index(索引)

C．cursor(游标)

D．view(视图)

答案

参考答案：B

解析：创建索引是加快表的查询速度，可以根据需要在基本表上建立一个或多个索引，从而提高系统的查询效率。

单项选择题

在票据当事人中，接受汇票出票人的付款委托同意承担支付票据义务的人称为（）。

A.背书人

B.付款人

C.承兑人

D.保证人
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单项选择题

The history of African—Americans during the past 400 years is traditionally narrated (1) an ongoing struggle against (2) and indifference on the part of the American mainstream, and a struggle (3) as an upward movement is (4) toward ever more justice and opportunity.

Technology in and of (5) is not at fault; it’s much too simple to say that gunpowder or agricultural machinery or fiber optics (6) been the enemy of an (7) group of people. A certain machine is put (8) work in a certain way—the purpose (9) which it was designed. The people who design the machines are not intent on unleashing chaos; they are usually trying to (10) a task more quickly, cleanly, or cheaply, (11) the imperative of innovation and efficiency that has ruled Western civilization (12) the Renaissance.

Mastery of technology is second only (13) money as the true measure of accomplishment in this country, and it is very likely that by (14) this under-representation in the technological realm, and by not questioning and examining the folkways that have (15) it, blacks are allowing. (16) to be kept out of the mainstream once again. This time, however, they will be (17) from the greatest cash engine of the twenty-first century. Inner-city blacks in particular are in danger, and the beautiful suburbs (18) ring the decay of Hartford, shed the past and learn to exist without contemplating or encountering the tragedy of the inner city.

And blacks must change as well. The ways that (19) their ancestors through captivity and coming to freedom have begun to loose their utility. If blacks (20) to survive as full participants in this society, they have to understand what works now.

14（）

A.totolerate

B.tolerate

C.tolerated

D.tolerating
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