问题 单项选择题 共用题干题

设有职工实体Employee(职工号,姓名,性别,年龄,通信地址,家庭成员),其中通信地址记录了邮编、省、市、街道信息;家庭成员记录了职工的亲属的姓名。职工实体中的通信地址是一个(1)属性;为了将数据库模式设计得更合理,对于家庭成员属性(2)。

空白(2)处应选择()

A.可以不作任何处理直接记录亲属的姓名

B.只允许记录一个亲属的姓名

C.需要对职工实体设置若干个亲属姓名字段

D.应该将职工的亲属的姓名加上职工号设计成为一个独立的实体

答案

参考答案:D

解析:简单属性是原子的,不可再分的。复合属性可以细分为更小的部分(即划分为别的属性)。有时用户希望访问整个属性,有时希望访问属性的某个成分,那么在模式设计时可采用复合属性。本题职工实体集Employee的通信地址可以进一步分为邮编、省、市、街道。第(1)空的正确答案为B。我们所举的例子中,定义的属性对于一个待定的实体都只有单独的一个值。例如,对于一个特定的职工,只对应一个职工号、职工姓名,这样的属性称为多值属性。为了将数据库模式设计得更合理,第(2)空的家庭成员属性应该将职工亲属的姓名加上职工号设计成为一个独立的实体。

阅读理解

A little boy invited his mother to attend his school’s first teacher-parent meeting. To the little boy’s dismay (沮丧), his mother said she would go. This would be the first time that his classmates and teachers met his mother and he was embarrassed by her appearance(出现). There was a severe (严重的) scar (伤疤) that covered nearly the whole right side of her face. The boy never wanted to talk about why or how she got the scar.

At the meeting, the people were impressed by the kindness of his mother with the scar, but the little boy was still embarrassed and hid himself from everyone. However, he could hear clearly the conversation between his mother and the teacher.

“How did you get the scar on your face?” the teacher asked.

The mother replied, “When my son was a baby, he was in a room that caught on fire. Everyone was too afraid to go in because the fire was out of control, but I went in. As I was running towards his bed, I saw a burning wood falling down and I placed myself over him trying to protect him. I was knocked to be unconscious (无知觉的), but luckily, a fireman came in and saved both of us.” She touched the burned side of her face. “This scar will be forever, but until today, I have never regretted doing what I did.”

When the little boy heard this, he couldn’t help running towards his mother with tears in his eyes. He hugged her and felt his mother was greater than anyone. He held her hand tightly for the rest of the day.

小题1:The underline world “embarrassed” means ______ in Chinese.

A.焦虑的

B.尴尬的

C.悲伤的

D.悔恨的小题2:In fact, the boy’s mother was ______.

A.beautiful

B.ugly

C.kind

D.ugly but kind小题3:We know from the passage that the little boy ______.

A.wasn’t moved by what her mother said

B.didn’t ask his mother to attend the meeting

C.wanted his mother to attend the meeting at first

D.didn’t really want his mother to attend the meeting at first小题4:After listening to his mother’s words about the scar, the boy might feel ______.

A.moved

B.unhappy

C.worried

D.dismay小题5:Which of the following is true?

A.The boy’s mother was brave but foolish

B.The boy hated what his mother had done

C.We should love our parents whatever they are like

D.The people at the meeting didn’t like the boy’s mother

选择题