问题 单项选择题

19~25题所用到的数据如表1和表2所示。

表1 课程表(KC.dbf)

课程号课程名学分
0001C程序设计5
0002数据结构6
0003计算机基础4
0004数据库应用基础4

表2 选课表(SKB.dbf)

学号课程号成绩
980001000198
980002000276
980001000250
980002000369
980003000175
980003000368
980004000155
980005000176
980004000265
9800030002J30
980003000486
980002000477

要列出所有课程的课程号、课程名和最高分,下列语句中正确的是______。

A.SELECT课程号,课程名,最高分FROM KC,SKB

B.SELECT KC.课程号,KC.课程名,SKB.最高分;
FROM KC,SKB WHERE KC.课程号=SKB.课程号

C.SELECT KC.课程号,KC.课程名,SKB.最高分;
FROM KC INNER JOIN SKB;
  ON KC.课程号=SKB.课程号;
 GROUP BY SKB.课程号

D.SELECT KC.课程号,KC.课程名,MAX(SKB.成绩) AS 最高分;
  FROM EC INNER JOIN SKB;
  ON KC.课程号=SKB.课程号;
  GROUP BY SKB.课程号

答案

参考答案:D

解析:

[分析]: 由于课程名字段和成绩字段分属于两个表,因此必须在两个表之间进行连接,显然可按照课程号相等进行连接。要求出每门课程的最高分,应用GROUP BY子句对课程号进行分组,并通过MAX()函数求出每个组的最高分。

阅读理解

任务型阅读。

     Life in the future will be different from life today. Between then and now many changes will take

place, but what will the changes be?

    The population is growing fast. There will be many people in the world and most of them will live

longer than people live now.

     Computers will be much smaller and more useful, and there will be at least one in every home.

And Computer Studies lessons will be one of the most important subjects in schools then.

     People will work _______ hours than they do now and they will have _____ free time for sports,

watching TV and travel. Traveling will be much cheaper and easier. And many more people will go to

other countries for holidays.

     There will be changes in our food, too. More land will be used for building new towns and houses

for all the people. Then there will be less room for cows and sheep, so meat will be more expensive.

Maybe no one will eat it every day. Instead they will eat more fruit and vegetables. Maybe people will

be healthier.

Work in the future will be different, too. Dangerous and hard work will be done by robots. Because

of this, many people will not have enough work to do. This will be a problem.

1. 在文中空格处填上适当的词 _________ _________

2. 将划线句子译成汉语

_________________________________________________

3. 找出同义句: Every family will have one computer or more.

_________________________________________________ 

4. 回答问题:What will be one of the most important subjects?

_________________________________________________

5. 找出或写出本文的主题句

_________________________________________________

单项选择题