表结构

实验内容

1

• 用SQL语句创建数据库CAP，数据文件名为CAPData.mdf，数据文件的初始存储空间大小为50M，最大存储空间为500M，存储空间自动增长量为10M。

CREATE DATABASE CAP
ON
(
NAME = CAP,
FILENAME = 'C:\Users\Zero\Desktop\CAPData.mdf', -- 文件名
SIZE = 50, -- 初始存储空间大小
MAXSIZE = 500,  -- 最大存储空间大小
FILEGROWTH = 10  -- 自动增长量
)

2

• 在CAP数据库中用SQL语句创建下面的4张表，合理设计每个字段的数据类型，建立主键与外键约束。表Products中的Price字段不允许为空。表Customers的discnt字段取值范围在[0,30]之间。利用SQL语句向表中添加表结构中的数据。

use CAP
CREATE TABLE Customers
(
"cid" char(4) CONSTRAINT Custom_Prim PRIMARY KEY,
"cname" varchar(10),
"city" varchar(10),
"discnt" numeric(4,2) CONSTRAINT DISCNT_CHK CHECK(discnt BETWEEN 0 AND 30)
)
CREATE TABLE Products
(
"Pid" char(3) CONSTRAINT Product_Prim PRIMARY KEY,
"pname" varchar(10),
"city" varchar(10),
"quantity" int,
"price" numeric(10,2) CONSTRAINT Price_NotNull NOT NULL
)
CREATE TABLE Agents
(
"Aid" char(3) CONSTRAINT Agent_Prim PRIMARY KEY,
"aname" varchar(10),
"city" varchar(10),
"percent" TINYINT
)
CREATE TABLE Orders
(
"OrDno" char(4) CONSTRAINT Order_Prim PRIMARY KEY,
"month" char(3) CONSTRAINT Month_CHK CHECK(month in ('Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec') ),
"cid" char(4) CONSTRAINT Cid_Fore FOREIGN KEY REFERENCES Customers(cid),
"aid" char(3) CONSTRAINT Aid_Fore FOREIGN KEY REFERENCES Agents(Aid),
"pid" char(3) CONSTRAINT Pid_Fore FOREIGN KEY REFERENCES Products(Pid),
"qty" int,
"dollars" numeric(10,2)
)

3

• 利用系统预定义的存储过程sp_helpdb查看数据库的相关信息，例如所有者、大小、创建日期等。

EXEC sp_helpdb

4

• 利用系统预定义的存储过程sp_helpconstraint查看表中出现的约束（包括Primary key, Foreign key, check constraint, default, unique）。

EXEC sp_helpconstraint Orders

5

• 创建一张表Orders_Jan，表的结构与Orders相同，将Orders表中month为‘Jan’的订单记录复制到表Orders_Jan中。

CREATE TABLE Orders_Jan
(
"OrDno" char(4) CONSTRAINT Order_Jan_Prim PRIMARY KEY,
"month" char(3) ,
"cid" char(4) CONSTRAINT Jan_Cid_Fore FOREIGN KEY REFERENCES Customers(cid),
"aid" char(3) CONSTRAINT Jan_Aid_Fore FOREIGN KEY REFERENCES Agents(Aid),
"pid" char(3) CONSTRAINT Jan_Pid_Fore FOREIGN KEY REFERENCES Products(Pid),
"qty" int,
"dollars" numeric(10,2)
);

INSERT INTO Orders_Jan
SELECT *
FROM Orders
WHERE month='Jan'

6

• 将Orders表中month为‘Jan’的订单记录全部删掉。

DELETE
FROM Orders
WHERE month='Jan'

7

• 对曾经下过金额（dollars）大于500的订单的客户，将其discnt值增加2个百分点（+2）。

UPDATE Customers
SET  discnt = discnt + 2  -- 更新discnt
WHERE cid IN(			-- 找出下过500订单的客户cid
SELECT DISTINCT cid -- 使用DISTINCT防止对同一个客户重复更新discnt
-- 其实可以直接SELECT cid , IN会自动去除重复值
FROM Orders
WHERE dollars > 500
)

8

• 写一段TSQL程序，向表Orders中增加5000条记录，要求订单尽可能均匀地分布在12个月中。

use CAP
DECLARE @i AS INT,@randNum AS FLOAT,@mon AS char(3),@OrdNo AS SMALLINT,@cid AS char(4),@aid AS char(3),@pid AS char(3),@price AS numeric(10,2);
SET @i=1;
SET @OrdNo=1030;
while @i<=5000  -- 流程控制，循环5000次
BEGIN
SET @randNum=RAND()*12;
SET @mon=							-- 随机产生月份
CASE
WHEN @randNum<1 THEN 'Jan'
WHEN @randNum>=1 AND @randNum<2 THEN 'Feb'
WHEN @randNum>=2 AND @randNum<3 THEN 'Mar'
WHEN @randNum>=3 AND @randNum<4 THEN 'Apr'
WHEN @randNum>=4 AND @randNum<5 THEN 'May'
WHEN @randNum>=5 AND @randNum<6 THEN 'Jun'
WHEN @randNum>=6 AND @randNum<7 THEN 'Jul'
WHEN @randNum>=7 AND @randNum<8 THEN 'Aug'
WHEN @randNum>=8 AND @randNum<9 THEN 'Sep'
WHEN @randNum>=9 AND @randNum<10 THEN 'Oct'
WHEN @randNum>=10 AND @randNum<11 THEN 'Nov'
ELSE 'Dec'
END

SELECT  @cid=cid 	-- 随机获取一个用户id
FROM Customers
ORDER BY NEWID()

SELECT @pid=Pid,@price=price	-- 随机获取一个产品id以及对应的产品价格
FROM Products
ORDER BY NEWID()

SET @aid=(SELECT TOP 1 Aid 			-- 随机获取一个代理商id
FROM Agents
ORDER BY NEWID()
)

SET @randNum=RAND()*2000+400;  -- 生成400至2400的随机订单数

INSERT INTO Orders				-- 插入一条订单记录
VALUES(CONVERT(char(4),@OrdNo),@mon,@cid,@aid,@pid,CONVERT(INT,@randNum),CONVERT(INT,@randNum) * @price);
-- 使用转换函数CONVERT()

SET @OrdNo=@OrdNo+1;
SET @i=@i+1;
END

9

• 在表Orders的’month’字段上建立索引。

CREATE INDEX Orders_Index
ON Orders(month)

10

• 创建一个视图order_month_summary，视图中的字段包括月份、该月的订单总量和该月的订单总金额。基于视图order_month_summary，查询第一季度各个月份的订单总量和订单总金额。

CREATE VIEW order_month_summary(month,total_qty,total_dollars)
AS SELECT month,SUM(qty),SUM(dollars)      -- 获得每月的总订单，总金额
FROM Orders
GROUP BY month

SELECT month,total_qty,total_dollars
FROM order_month_summary
WHERE month IN ('Jan','Feb','Mar')     -- 查询第一季度