SQL Server 2008 存储过程示例 |
--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<8 --查询并联合两临时表 select * from #DU_User2 where ID<3 union select * from #DU_User1 --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 @a<=100 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: --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: --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 |