由于关系模式设计不当所引起的插入异常指的是A.两个事务并发地对同一关系进行插入而造成

题型:单项选择题

问题:

由于关系模式设计不当所引起的插入异常指的是

A.两个事务并发地对同一关系进行插入而造成数据库不一致

B.由于码值的一部分为空而不能将有用的信息作为一个元组插入到关系中

C.未经授权的用户对关系进行了插入

D.插入操作因为违反完整性约束条件而遭到拒绝

考点:计算机等级考试数据库技术三级数据库技术笔试
题型:单项选择题

糖尿病患者

A.高蛋白、高热量、高脂肪、高维生素饮食
B.低糖、低脂肪、高蛋白、高纤维素饮食
C.高蛋白、高糖、高维生素、高钠低钾饮食
D.低脂肪、低热量、少盐、粗纤维、富含维生素饮食
E.高蛋白、高维生素、低碳水化合物、低脂肪、低盐、富含钾、钙饮食

题型:单项选择题

阅读理解.

     The Beatles were the most influential band in pop history. In their 8year, 12album

history, Paul McCartney, John Lennon, George Harrison and Ringo Starr altered (改变)

popular culture dramatically. And it wasn't just the suits and changing lengths of hair the

four Liverpool boys wore that had such an impact, but what they seemed to stand for.

The world saw them as the voice of a new generation, one with a very different attitude

to life.

     Their influence was at its height in the 1960s, but their music continues to stir listeners

today. However, up until recently one aspect of the Beatles was struck in Yesterday: The

music had never been remastered (重新灌录). But on September 9 that situation came to

an end, with the release of the entire band's music in a digital makeover. It is probably the

biggest reissue (重新发行) in pop music history, said British newspaper the Financial

Times.

     The albums were remastered at Abbey Road Studios in London, the location where the

band produced much of their work. The cover of their last album, Abbey Road of 1969,

featured the four young men striding (大步行走) across a zebra crossing on Abbey Road

itself. It is one of the most famous of all Beatles images.

     Recently, to celebrate the 40th anniversary of the album, hundreds of Beatles lovers

gathered there to show their appreciation.

     Pop groups come and go. The boy band pursued by screaming fans one year will be

forgotten the next. But the Beatles are one of the few groups whose music seems to have

endured (持久). Why? Paul McCartney's biographer Barry Miles has an explanation: "They

were the first rock band… and they just happened to be the best. They were the first band

to play stadiums, to have their own products. They were groundbreaking in every way," he

says.

1.Why did the Beatles change popular culture?______.

A.Because of the suits of the four Liverpool boys.

B.Because of changing lengths of hair the four Liverpool boys wore.

C.Because of their albums.

D.Because of their different attitude to life.

2.Which of the following statements is FALSE according to the second paragraph?______.

A.The Beatles influenced people at its height in the 1960s.

B.Their music Yesterday had never been remastered.

C.The entire band's music in a digital makeover will be remastered.

D.On September 9, their music came to an end.

3.What is their last album?______.

A.Yesterday.

B.Abbey Road of 1969.

C.Come Together.

D.In My life.

4.What is NOT the reason why their music can endure?______.

A.They were the first rock band.

B.They were the best one.

C.They were the first band to play stadiums and to have their own works.

D.They wore special suits.

5.What's the main idea of the passage?______.

A.What is the Beatles?

B.Legendary band stays on top in digital times.

C.The origin of the Beatles.

D.Why is the Beatles popular with people?

题型:单项选择题

()是利用一家以上、但又不是让所有愿意经销的几家机构都来经营某一种特定产品。

A.专营性分销

B.密集性分销

C.选择性分销

D.差别化分销

题型:单项选择题

旅游客运的特点是()

A.载客人数少、灵活方便

B.多为往返包车,旅游班车的起点也是终点

C.固定客运站和停靠站(定点)

D.服务对象以团体为主,行驶路线、乘车时间和地点、途中停止,由用户选择确定,费用结算为一车一票或多车一票

题型:单项选择题

常见的液力变矩器由可旋转的()和(),以及固定不动的()三个元件组成。

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