--创建数据库
CREATE DATABASE SQLTest
ON
(NAME=SQLTest_date,FILENAME='E:\数据库\SQLTest.mdf',SIZE=3,FILEGROWTH=1
)
LOG ON
(NAME=SQLTest_log,FILENAME='E:\数据库\SQLTest.ldf',SIZE=1,FILEGROWTH=1
)
GO--删除数据库
DROP DATABASE SQLTest--修改数据库(重命名)
ALTER DATABASE SQLTest
MODIFY name=Test--备份数据库
BACKUP DATABASE SQLTest TO DISK ='E:\数据库\SQLTest.bak'--还原数据库
RESTORE DATABASE SQLTest FROM DISK='E:\数据库\SQLTest.bak'--创建数据库中的表
USE SQLTest
CREATE TABLE Teacher
(
Id INT IDENTITY(1,1) NOT NULL,
Name VARCHAR(20) NOT NULL,
Sex CHAR(2) NULL,
Phone VARCHAR(20) NOT NULL,
Address VARCHAR(100) NULL,
Email VARCHAR(30) NULL
)--删除数据库中的表
DROP TABLE Teacher--更新数据库中的表
--添加字段
ALTER TABLE Teacher
ADD Sallary smallmoney null--删除字段
ALTER TABLE Teacher
DROP COLUMN Sallary--修改字段
ALTER TABLE Teacher
ALTER COLUMN Phone VARCHAR(12) NULL--数据安全性
--创建规则
CREATE RULE SEX_RULE AS @Sex IN('男','女')
GO--使用规则
EXECUTE sp_bindrule 'SEX_RULE','Teacher.Sex'--解除规则
EXECUTE sp_unbindrule 'Teacher.Sex'--删除规则
DROP RULE SEX_RULE--数据添加
INSERT INTO Teacher VALUES('Tom','男','145656789','sdkjagfi','jkgsdhlfuihl',2000)
INSERT INTO Teacher (Name,Sex) VALUES('Juery','男')--数据删除(无条件会删除所有元组)
DELETE FROM Teacher WHERE Id='02'--数据更新(无条件会更新所有元组)
UPDATE Teacher SET Sex='女' WHERE Name='Jack'--数据查询
--查询所有列
SELECT * FROM Teacher--查询指定列
SELECT Name,Sex FROM Teacher--在查询指定列中使用表达式
SELECT Name,Sex,Sallary*1.2 AS Sallary FROM Teacher--重新命名结果列名
SELECT Name AS 姓名 FROM Teacher
SELECT 姓名=Name FROM Teacher--将查询的表生成一个新表
SELECT Name,Sex INTO NEWTeacher FROM Teacher--取出查询结果的部分内容
SELECT TOP 10 * FROM Teacher--使用逻辑表达式进行查询
SELECT * FROM Teacher WHERE Sallary<=1000 OR Sallary>=3000
SELECT * FROM Teacher WHERE Sallary>1000 AND Sallary<3000
SELECT * FROM Teacher WHERE NOT(Sallary>3000)--使用通配符进行模糊查询
SELECT * FROM Teacher WHERE Name LIKE '_ac%'
SELECT * FROM Teacher WHERE Name LIKE '[J,T]%'--使用BETWEEN...AND关键字进行查询
SELECT * FROM Teacher WHERE PostDate BETWEEN '2012-12-01' AND DATEADD (DAY ,3, '2012-12-01')--使用IN关键字进行查询
SELECT * FROM Teacher WHERE Sex IN ('男','女')
SELECT * FROM Teacher WHERE Sex IN (SELECT Sex FROM Teacher GROUP BY Sex)--使用NULL关键字进行查询
SELECT * FROM Teacher WHERE Name IS NOT NULL--排序查询
SELECT * FROM Teacher ORDER BY Sallary ASC
SELECT * FROM Teacher ORDER BY Sallary DESC--分组查询
SELECT Email FROM Teacher GROUP BY Email
SELECT Sex, COUNT(Name) AS Count FROM Teacher GROUP BY Sex HAVING Sex='男'--使用聚集函数查询
SELECT COUNT(*) AS 总个数 FROM Teacher --"*"包括空值行
SELECT SUM(Sallary) AS 总和 FROM Teacher
SELECT AVG(Sallary) AS 平均数 FROM Teacher
SELECT MAX(Sallary) AS 最大值 FROM Teacher
SELECT MIN(Sallary) AS 最小值 FROM Teacher--多表连接查询
--内连接
SELECT Teacher.Name,Course.Name FROM Teacher,Course WHERE Teacher.Id=Course.TeacherId
SELECT Teacher.Name,Course.Name FROM Teacher INNER JOIN Course ON Teacher.Id=Course.TeacherId--外连接
SELECT Teacher.Name,Course.Name FROM Teacher FULL OUTER JOIN Course ON Teacher.Id=Course.TeacherId
SELECT Teacher.Name,Course.Name FROM Teacher LEFT OUTER JOIN Course ON Teacher.Id=Course.TeacherId
SELECT Teacher.Name,Course.Name FROM Teacher RIGHT OUTER JOIN Course ON Teacher.Id=Course.TeacherId--循环控制语句
--WHILE语句
DECLARE @num int
SELECT @num=0
WHILE @num<10
BEGIN
SELECT @num=@num+1
SELECT @num
END--GOTO语句
BEGIN
SELECT Name FROM Teacher
GOTO SKIP
SELECT * FROM Teacher
SKIP:
PRINT 'SELECT * FROM Teacher did not get excuted'
END--IF...ELSE语句
DECLARE @X INT, @Y INT,@Z INT
SELECT @X=2,@Y=5,@Z=4
IF @X>@Y
PRINT 'X>Y'
ELSE IF @Y>@Z
PRINT 'Y>Z'
ELSE
PRINT 'Z>Y'--CASE语句
SELECT Sallary,
CASE
WHEN Sallary>=3000 THEN 'VERYGOOD'
WHEN Sallary>=2000 THEN 'GOOD'
ELSE 'BAD'
END
FROM Teacher--WHILE语句
DECLARE @I INT
SET @I=5
WHILE @I>-1
BEGIN
PRINT @I
SET @I=@I-1
IF @I=1
BREAK
END--WAITFOR语句
SELECT * FROM Teacher WAITFOR DELAY '00:00:10'--10秒后执行
SELECT * FROM Teacher WAITFOR TIME '00:00:10'--直到00:00:10才执行--常用函数
--CHARINDEX函数
SELECT CHARINDEX ('a','I have many friends')
SELECT CHARINDEX('a','I hava many friends',5)--LEFT函数
SELECT LEFT('I hava many friends',10)--RIGHT函数
SELECT RIGHT('I have many friends',10)--LEN函数
SELECT LEN('I have many friends')--LTRIM函数
SELECT LTRIM('  I have many friends')--RTRIM函数
SELECT RTRIM('I have many friends   ')--LOWER函数
SELECT LOWER('I Have Many Friends')--UPPER函数
SELECT UPPER('I have many friends')--PATINDEX函数(字符串中的第一个a)
SELECT PATINDEX('%a%','I have many friends')--REPALCE函数(替换)
SELECT REPLACE ('He is a student','student','teacher')--REVERSE函数(反转)
SELECT REVERSE('ABCDEFG')--STR函数
SELECT STR(123.45)
SELECT STR(123.45,6,2)--SUBSTRING函数
SELECT SUBSTRING('I have many friends',1,LEN('I have many friends')/2)--DATEADD函数
SELECT DATEADD(DAY,2,'2012-12-05')--DATENAME函数
SELECT DATENAME(WEEKDAY,'2012-12-05') AS 星期几--DATEPART函数
SELECT DATEPART(WEEKDAY,'2012-12-05') AS 星期的第几天--DAY函数
SELECT DAY('2012-12-05') AS 天--MONTH函数
SELECT MONTH('2012-12-05') AS 月--YEAR函数
SELECT YEAR('2012-12-05') AS 年--GETDATE函数
SELECT GETDATE() AS 目前时间
SELECT YEAR (GETDATE())--CAST函数(数据类型转换)
SELECT CAST('010101' AS DATETIME) AS 日期年月日
SELECT CAST('010101' AS FLOAT) AS '0不见了'--CONVERT函数(数据格式转换)
SELECT CONVERT(VARCHAR(8),GETDATE(),1) AS 日期
SELECT CONVERT(VARCHAR(8),GETDATE(),8) AS 时间--事务
--显示事务
USE SQLTest
BEGIN TRANSACTION TA
INSERT INTO Teacher (Name,Sex) VALUES ('LILEI','男')
INSERT INTO Teacher (Sex) VALUES('女')
ROLLBACK TRANSACTION
SELECT * FROM Teacher--隐式事务
SET IMPLICIT_TRANSACTIONS ON --隐式事务不需要BEGIN TRANSACTION
INSERT INTO Teacher (Name,Sex) VALUES ('LILEI','男')
COMMIT TRANSACTION
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
ROLLBACK TRANSACTION
SELECT * FROM Teacher
SET IMPLICIT_TRANSACTIONS OFF --自动处理事务
INSERT INTO Teacher (Name,Sex) VALUES ('LILEI','男')
COMMIT TRANSACTION
BEGIN TRANSACTION --不再是隐式事务
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
ROLLBACK TRANSACTION
SELECT * FROM Teacher--事务案例
BEGIN TRANSACTION
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
INSERT INTO Teacher (Name,Sex) VALUES ('LILI','女')
DECLARE @COUNT INT
SET @COUNT=(SELECT COUNT(Name) FROM Teacher WHERE Name='LILI')
IF @COUNT>4
BEGIN
ROLLBACK TRANSACTION
PRINT '数据过多，失败！'
SELECT * FROM Teacher
END
ELSE
BEGIN
COMMIT TRANSACTION
PRINT '数据添加成功！'
SELECT * FROM Teacher
END--锁
--查看系统锁
EXECUTE sp_lock--锁定表的某一行
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
SELECT * FROM Teacher ROWLOCK WHERE Id=5--锁定整个表
SELECT * FROM Teacher TABLOCK WHERE 1=1--排它锁
BEGIN TRANSACTION TRAN1
UPDATE Teacher SET Phone='5842156624' WHERE Name='LILI'
WAITFOR DELAY '00:00:10'
COMMIT TRANSACTION
BEGIN TRANSACTION TRAN2
SELECT * FROM Teacher WHERE Name='LILI'
COMMIT--共享锁
BEGIN TRANSACTION TRAN1
SELECT * FROM Teacher WITH(HOLDLOCK)
WAITFOR DELAY '00:00:10'
COMMIT TRANSACTION
BEGIN TRANSACTION TRAN2
SELECT Name,Sex FROM Teacher
UPDATE Teacher SET Phone='111111111' WHERE Name='LILI'
COMMIT TRANSACTION--死锁
BEGIN TRANSACTION TRAN1
UPDATE Teacher SET Phone='33333333' WHERE Name='LILEI'
WAITFOR DELAY '00:00:10'
UPDATE Teacher SET Phone='44444444' WHERE Name='LILI'
COMMIT TRAN
BEGIN TRAN TRAN2
UPDATE Teacher SET Phone='44444444' WHERE Name='LILI'
WAITFOR DELAY '00:00:10'
UPDATE Teacher SET Phone='33333333' WHERE Name='LILEI'
COMMIT TRANSACTION--存储过程
--创建存储过程
CREATE PROCEDURE SELECTBYSEX
@COUNTS INT OUTPUT
AS
BEGIN
SET NOCOUNT ON
SET @COUNTS=(SELECT COUNT(*) FROM Teacher WHERE Sex='女')
END
GO--执行存储过程
DECLARE @COUNTS INT
EXECUTE SELECTBYSEX @COUNTS OUTPUT
PRINT @COUNTS
GO--查看存储过程
EXECUTE sp_help SELECTBYSEX
GO--删除存储过程
DROP PROCEDURE SELECTBYSEX
GO