存储过程的拼接写法 -- 转载

USE [a]
GO
/****** Object:  StoredProcedure [a].[Processname]    Script Date: 02/24/2011 11:49:55 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author:		<Author,,Name>
-- Create date: <Create Date,,>
-- Description:	<Description,,>
-- =============================================
CREATE PROCEDURE [a].[Processname]
@FromDateTime varchar(200),
@ToDateTime varchar(200),
@CountryCode varchar(200),
@Version varchar(200)
AS
declare @sql varchar(1000)
set @sql='select AccessDateTime,IpAddress,Area,AreaDetail as description,City,Version from a.TableName where AccessDateTime
between ''' + @FromDateTime+''' and '''+ @ToDateTime+''''
BEGIN
if(@CountryCode='')
begin
set @sql=@sql
if(@Version='')
begin
set @sql = @sql +' order by id desc'
end
else
begin
set @sql = @sql + ' and  Version='''+@Version +'''  order by id desc'
end
end
else
begin
set @sql=@sql
if(@Version='')
begin
set @sql=@sql +' and  Area='''+@CountryCode+''' order by id desc'
end
else
begin
set @sql=@sql +' and Area='''+@CountryCode+''' and  Version='''+ @Version +''' order by id desc'
end
end
--print @sql
exec(@sql)
END