试题与答案

设有关系模式S(Sno, Sname, Pno, Pname, Q, A)表示销售员

题型:单项选择题

题目:

设有关系模式S(Sno, Sname, Pno, Pname, Q, A)表示销售员销售商品情况,其中各属性的含义是:Sno为销售员员工号,Sname为销售员姓名,Pno为商品号,Pname为商品名称,Q为销售商品数目,A为销售商品总金额,根据定义有如下函数依赖集:P=Sno→Sname,Sno→Q,Sno→A,Pno→Pname

关系模式S的关键字是(1),W的规范化程度最高达到(2)。若将关系模式S分解为3个关系模式$1(Sno, Sname, Q, A), S2(Sno, Pno, Pname),则S1的规范化程度最高达到(3),S2的规范化程度最高达到(4)

SQL中集合成员资格的比较操作“元组IN(集合)”中的“IN”与(5)操作符等价。

(1)是()

A.Sno

B.Pno

C.(Sno,Pno)

D.(Sno,Pno,Q)

答案:

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参考答案:start drinking

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题型:阅读理解

阅读理解。

     April Fools' Day is supposed to be a day to play jokes on others in hopes of getting a good laugh and

making one feel like a fool. However, the April Fools' Day of 2010 was quite different for my mom and me.

     That day my friend Jimmy and I were playing a game. I had dropped down from a bar (横木) many

times in the past without ever having a problem, but that day the simple act of dropping to the ground became

a nightmare (噩梦). I broke my arm.

     Jimmy's dad heard my crying and rushed out to see what was going on. When he saw the problem, he

quickly put me into his truck and went inside to telephone my mom and let her know he would take me to

the hospital. As that day was April Fools' Day, Mom was not buying it and really thought all this was a big

joke. Mom was finally convinced by Jimmy's mom. When she saw me, she broke down in tears because

she felt so bad-she originally (开始) thought this was just a big prank (恶作剧).

     I guess one could compare this to the story of "The Boy Who Cried Wolf". Since I had pulled pranks

before, it is no wonder that my mom didn't believe it. I as well as my mom was made to look like a fool

that day. We both learned a valuable lesson.

1. What happened to the writer on the April Fools' Day of 2010?

A. He dreamed a terrible dream.

B. He was hurt by Jimmy.

C. He had an accident.

D. He fooled his mom with his friend.

2. Why did Jimmy's dad phone the writer's mom?

A. Because he wanted to play a joke on her.

B. Because he wanted her to go to the hospital to pay the money.

C. Because he wanted to see how deeply she loved her son.

D. Because he wanted to inform her of the accident.

3. What does the underlined sentence "Mom was not buying it" mean?

A. She didn't believe what Jimmy's dad said.

B. She would not like to pay the money.

C. She had no preparation for the bad news.

D. She thought her son deserved (应受) it.

4. Why did the writer mention the story of "The Boy Who Cried Wolf"?

A. Because he thought it was his mom's fault.

B. Because he had a lesson like that.

C. Because he was proud of his story.

D. Because he felt he was luckier than that boy.

5. From the passage we can infer that __________.

A. the writer's mom didn't care much about him

B. the writer was a dishonest person

C. the writer won't pull pranks as before

D. the writer will lose interest in games

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