数据库2008安装教程 SQL,Server,2008,数据库教程

--有输入参数的存储过程--

create proc GetComment

(@commentid int)

as

select * from Comment where CommentID=@commentid

--有输入与输出参数的存储过程--

create proc GetCommentCount

@newsid int,

@count int output

as

select @count=count(*) from Comment where NewsID=@newsid

--返回单个值的函数--

create function MyFunction

(@newsid int)

returns int

as

begin

declare @count int

select @count=count(*) from Comment where NewsID=@newsid

return @count

end

--调用方法--

declare @count int

exec @count=MyFunction 2

print @count

--返回值为表的函数--

Create function GetFunctionTable

(@newsid int)

returns table

as

return

(select * from Comment where NewsID=@newsid)

--返回值为表的函数的调用--

select * from GetFunctionTable(2)

SQLServer 存储过程中不拼接SQL字符串实现多条件查询

--以前拼接的写法

set @sql=" select * from table where 1=1 "

if (@addDate is not null)

set @sql = @sql+" and addDate = "+ @addDate + " "

if (@name "" and is not null)

set @sql = @sql+ " and name = " + @name + " "

exec(@sql)

下面是 不采用拼接SQL字符串实现多条件查询的解决方案

--第一种写法是 感觉代码有些冗余

if (@addDate is not null) and (@name "")

select * from table where addDate = @addDate and name = @name

else if (@addDate is not null) and (@name ="")

select * from table where addDate = @addDate

else if(@addDate is null) and (@name "")

select * from table where and name = @name

else if(@addDate is null) and (@name = "")

select * from table

--第二种写法是

select * from table where (addDate = @addDate or @addDate is null) and (name = @name or @name = "")

--第三种写法是

SELECT * FROM table where

addDate = CASE @addDate IS NULL THEN addDate ELSE @addDate END,

name = CASE @name WHEN "" THEN name ELSE @name END

SQLSERVER存储过程基本语法

一、定义变量

--简单赋值

declare @a int

set @a=5

print @a

--使用select语句赋值

declare @user1 nvarchar(50)

select @user1= "张三"

print @user1

declare @user2 nvarchar(50)

select @user2 = Name from ST_User where ID=1

print @user2

--使用update语句赋值

declare @user3 nvarchar(50)

update ST_User set @user3 = Name where ID=1

print @user3

二、表、临时表、表变量

--创建临时表1

create table #DU_User1

(

[ID] [ int ] NOT NULL ,

[Oid] [ int ] NOT NULL ,

[Login] [nvarchar](50) NOT NULL ,

[Rtx] [nvarchar](4) NOT NULL ,

[ Name ] [nvarchar](5) NOT NULL ,

[ Password ] [nvarchar]( max ) NULL ,

[State] [nvarchar](8) NOT NULL

);

--向临时表1插入一条记录

insert into #DU_User1 (ID,Oid,[Login],Rtx, Name ,[ Password ],State) values (100,2, "LS" , "0000" , "临时" , "321" , "特殊" );

--从ST_User查询数据，填充至新生成的临时表

select * into #DU_User2 from ST_User where ID

--查询并联合两临时表

select * from #DU_User2 where ID

--删除两临时表

drop table #DU_User1

drop table #DU_User2

--创建临时表

CREATE TABLE #t

(

[ID] [ int ] NOT NULL ,

[Oid] [ int ] NOT NULL ,

[Login] [nvarchar](50) NOT NULL ,

[Rtx] [nvarchar](4) NOT NULL ,

[ Name ] [nvarchar](5) NOT NULL ,

[ Password ] [nvarchar]( max ) NULL ,

[State] [nvarchar](8) NOT NULL ,

)

--将查询结果集(多条数据)插入临时表

insert into #t select * from ST_User

--不能这样插入

--select * into #t from dbo.ST_User

--添加一列，为int型自增长子段

alter table #t add [myid] int NOT NULL IDENTITY(1,1)

--添加一列，默认填充全球唯一标识

alter table #t add [myid1] uniqueidentifier NOT NULL default (newid())

select * from #t

drop table #t

--给查询结果集增加自增长列

--无主键时：

select IDENTITY( int ,1,1) as ID, Name ,[Login],[ Password ] into #t from ST_User

select * from #t

--有主键时：

select ( select SUM (1) from ST_User where ID a.ID) as myID,* from ST_User a order by myID

--定义表变量

declare @t table

(

id int not null ,

msg nvarchar(50) null

)

insert into @t values (1, "1" )

insert into @t values (2, "2" )

select * from @t

三、循环

--while循环计算1到100的和

declare @a int

declare @ sum int

set @a=1

set @ sum =0

while @a100

begin

set @ sum +=@a

set @a+=1

end

print @ sum

四、条件语句

--if,else条件分支

if(1+1=2)

begin

print "对"

end

else

begin

print "错"

end

--when then条件分支

declare @today int

declare @week nvarchar(3)

set @today=3

set @week= case

when @today=1 then "星期一"

when @today=2 then "星期二"

when @today=3 then "星期三"

when @today=4 then "星期四"

when @today=5 then "星期五"

when @today=6 then "星期六"

when @today=7 then "星期日"

else "值错误"

end

print @week

五、游标

declare @ID int

declare @Oid int

declare @Login varchar (50)

--定义一个游标

declare user_cur cursor for select ID,Oid,[Login] from ST_User

--打开游标

open user_cur

while @@fetch_status=0

begin

--读取游标

fetch next from user_cur into @ID,@Oid,@Login

print @ID

--print @Login

end

close user_cur

--摧毁游标

deallocate user_cur

五、游标

declare @ID int

declare @Oid int

declare @Login varchar (50)

--定义一个游标

declare user_cur cursor for select ID,Oid,[Login] from ST_User

--打开游标

open user_cur

while @@fetch_status=0

begin

--读取游标

fetch next from user_cur into @ID,@Oid,@Login

print @ID

--print @Login

end

close user_cur

--摧毁游标

deallocate user_cur

六、触发器

触发器中的临时表：

Inserted

存放进行insert和update 操作后的数据

Deleted

存放进行delete 和update操作前的数据

--创建触发器

Create trigger User_OnUpdate

On ST_User

for Update

As

declare @msg nvarchar(50)

--@msg记录修改情况

select @msg = N "姓名从" + Deleted. Name + N "修改为" + Inserted. Name + "" from Inserted,Deleted

--插入日志表

insert into [LOG](MSG) values (@msg)

--删除触发器

drop trigger User_OnUpdate

七、存储过程

--创建带output参数的存储过程

CREATE PROCEDURE PR_Sum

@a int ,

@b int ,

@ sum int output

AS

BEGIN

set @ sum =@a+@b

END

--创建Return返回值存储过程

CREATE PROCEDURE PR_Sum2

@a int ,

@b int

AS

BEGIN

Return @a+@b

END

--执行存储过程获取output型返回值

declare @mysum int

execute PR_Sum 1,2,@mysum output

print @mysum

--执行存储过程获取Return型返回值

declare @mysum2 int

execute @mysum2= PR_Sum2 1,2

print @mysum2

八、自定义函数

函数的分类：

1)标量值函数

2)表值函数

a:内联表值函数

b:多语句表值函数

3)系统函数

--新建标量值函数

create function FUNC_Sum1

(

@a int ,

@b int

)

returns int

as

begin

return @a+@b

end

--新建内联表值函数

create function FUNC_UserTab_1

(

@myId int

)

returns table

as

return ( select * from ST_User where ID@myId)

--新建多语句表值函数

create function FUNC_UserTab_2

(

@myId int

)

returns @t table

(

[ID] [ int ] NOT NULL ,

[Oid] [ int ] NOT NULL ,

[Login] [nvarchar](50) NOT NULL ,

[Rtx] [nvarchar](4) NOT NULL ,

[ Name ] [nvarchar](5) NOT NULL ,

[ Password ] [nvarchar]( max ) NULL ,

[State] [nvarchar](8) NOT NULL

)

as

begin

insert into @t select * from ST_User where ID@myId

return

end

--调用表值函数

select * from dbo.FUNC_UserTab_1(15)

--调用标量值函数

declare @s int

set @s=dbo.FUNC_Sum1(100,50)

print @s

--删除标量值函数

drop function FUNC_Sum1