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阅读以下说明，回答问题1-3。在图书馆数据库有三个基本表：书目表Cata(书号Cno、书名Cname、作者Cauthor、出版年Cdate、价格Cprice)、学生表Student(学号Sno、姓名Sname、性别Sgender、专业Sdept)和借书历史表Borrow(所借书号Cno、借书者学号Sno、借书日期Bbdate、还书日期Brdate)。 [问题2] 请用SQL实现如下操作： (1)图书馆里已有的鲁迅著作的名称 (2)按借书日期列出学生李明的所借书名 (3)往学生表Student中插入一个学生记录。(学号：132，姓名：张华，性别：男，系别：计算机) (4)把《野火集》的价格修改为15元

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阅读以下说明，回答问题1-4。现有这样一个关系，用来表示某工厂工人家庭的信息。记录每个工人的工作证号、姓名和家庭住址，还包含他/她的每个孩子的身份证号、姓名和年龄，以及他／她所拥有的每部电话的电话号码和型号。已知：有一些人可能有很多部电话，这些电话可能是同一型号，也可能不是同一型号；有一些人没有电话；如果某人有电话，他的每部电话都有一个电话号码。有一些人可能有很多个孩子，有一些人没有孩子。初步设计的关系模式如下：R(身份证号，姓名，家庭住址，H身份证号，H姓名，H年龄，电话号码，型号)，其中“H身份证号，H姓名，H年龄”分别是孩子的身份证号、姓名和年龄。 [问题1] 请将该关系模式分解成第二范式的关系模式，确定主关系键。

内部网络经由防火墙采用NAT方式与外部网络通信，为下表中(5)～(7)空缺处选择正确答案，填写在答题纸的相应位置。源地址源端口目的地址协议转换接口转换后地址 192.168.1.1/24Any(5)Any(6)(7)

A.

E1

B.

E2

C.

E3

There is an old saying in English: "Laughter is the best medicine". Until recently, few people took the saying very seriously. Now, however, doctors have begun to investigate laughter and the effects it has on the human body. They have found evidence that laughter really can improve people’s health.Tests were carried out to study the effects of laughter on the body. People watched funny films, while doctors checked their heart rate, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart rate and the rate of breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.Other tests have shown that laughter appears to be capable of reducing the effect of pain on the body.There is also some evidence to suggest that laughter helps the body’s immune system, that is, the system which fights infection.As a result of these discoveries, some doctors and psychiatrists (精神病学家)in the United States now hold laughter clinics, in which they try to improve their patients’ condition by encouraging them to laugh.1) Laughter really can (46) .2) In the first test, it was found that laughter has similar effects to (47) .3) Other tests have shown that laughter can reduce the effect of (48) on the body.4) There is evidence to show that laughter helps the body’s (49) .5) In the clinics, the psychiatrists try to improve their patients’ condition by encouraging them (50) . 49（）

内部网络经由防火墙采用NAT方式与外部网络通信，为下表中(5)～(7)空缺处选择正确答案，填写在答题纸的相应位置。源地址源端口目的地址协议转换接口转换后地址 192.168.1.1/24Any(5)Any(6)(7)

A.

192.168.1.1

B.

210.156.169.6

C.

211.156.169.6