问题 单项选择题

现有表:读者(读者姓名,读者单位,借书证号)
借阅(借书证号,图书名称,图书作者,出版单位)
从读者表和借阅表中查询借阅了两本及两本以上图书的读者姓名和读者单位,正确的SQL语句是

A) SELECT 读者姓名,读者单位 FROM 读者 WHERE 借书证号 IN;
(SELECT 借书证号 FROM 借阅 GROUP BY 借书证号 HAVING COUNT(*)>=2)
B) SELECT 读者姓名,读者单位 FROM 读者 WHERE 借书证号 EXISTS;
(SELECT 借书证号 FROM 借阅 GROUP BY 借书证号 HAVING COUNT(*)>=2)
C) SELECT 读者姓名,读者单位 FROM 读者 WHERE 借书证号IN;
(SELECT 借书证号 FROM 借阅 GROUP BY 借书证号 WHERE COUNT(*)>=2)
D) SELECT 读者姓名,读者单位 FROM 读者 WHERE 借书证号 EXISTS;
(SELECT 借书证号 FROM 借阅 GROUP BY 借书证号 WHERE COUNT(*)>=2)

答案

参考答案:A

解析: 本题考查了SQL查询功能的嵌套查询和分组与计算查询。分组与计算查询中,利用HAVING进一步限定分组的条件。HAVINC子句和WHERE子句不矛盾,在查询中是先用WHERE子句限定元组,然后进行分组,最后再用HAVING子句限定分组。

单项选择题
阅读理解

In 1990 Peter Salovey Ph. D and John Mayer Ph. D coined the term Emotional Intelligence. Their research has opened many people’s eyes to the fact that EQ or emotional quotient holds the key to one’s happiness and well being, and helped us to realize that our emotional makeup can be so much more important than our mental, or what we refer to as IQ—intelligent quotient.

IQ is essential for learning and mental development and EQ is much more important for happiness and success. Some time ago a study done in the United States proved that doctors who were impatient and did not exhibit much care towards their patients were more likely to be sued (起诉) for malpractice(渎职), whereas doctors who were caring and attentive to their patients were less likely to be sued even if they made a critical mistake. A woman wrote to newspaper recently telling about her brother. He was apparently a genius but did not get along with people, quit every job he started, and eventually became a taxi driver. These are just a few examples of people with high IQ but low EQ.

We have all known people who did not complete college, but who have become very successful in business. We call them street smart. We also know people who, on the whole, are positive, communicative, pleasant and supportive—these people enjoy a high level of EQ.

Many people wish to improve their EQ for the purpose of becoming happier, more successful, and at the same time more balanced, individuals. The remarkable thing about EQ is that it can always, at any age, be improved, unlike IQ, which remains more or less fixed in adult life.

Now psychologists start workshops focusing on showing people how to increase their EQ. This enables them to accomplish their dreams and desires, rid themselves of negative patterns and shows them that once they master their inner world, their outer world becomes much better.

47. In the second paragraph, the author gives us two examples to show that _____.

A. doctors in the United States are often involved in cases

B. working as a taxi driver in the United States requires high EQ

C. those with high IQ are often engaged in the low-rank work

D. those with low EQ have a harder time surviving in life

48. Which of the following can’t be used to describe the people with a high level of EQ?

A. They are positive, communicative, pleasant and supportive.

B. They are optimistic and untroubled by difficulties.

C. They are impatient and show little care towards others.

D. They may be very successful in business.

49. It can be inferred that predicting future successes, ______.

A. a person’s brainpower might actually matter less than a person’s character

B. a person’s IQ might be more important than a person’s EQ

C. IQ plays an important role as well as EQ

D. both IQ and EQ are the key points that should be considered

50. Which of following is NOT true according to the passage?

A. People with high IQ are likely to gain knowledge quickly.

B. At work EQ gets you hired easily and IQ gets you promoted.

C. Having a high IQ will help us in some ways but having a high EQ might help us even more.

D. People’s EQ could be raised much more than their IQ.