SQL备份数据库

USE [master]
GO
/****** 对象:  StoredProcedure [dbo].[DataBaseRestore]    脚本日期: 12/18/2015 14:17:11 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

ALTER PROCEDURE [dbo].[DataBaseRestore]
AS

declare @device varchar(255)
declare @path varchar(255)
declare @dbname varchar(255)
declare @filename varchar(255)
declare @cmd varchar(255)

set @dbname = 'SmartPas'
set @path = 'D:\database\' --备份文件存储位置
set @filename = @dbname+'_Ts_'+ convert(char(8),getdate(),112)+substring(replace(convert(char(9),getdate(),114),':',''),0,3)+'.bak'
set @device=@path + @filename
declare @sql nvarchar(4000),@par nvarchar(1000)
if not exists(
select * from master..sysdatabases
where name=@dbname
)
begin
--select @flag='db not exist'  /*数据库不存在*/
return 2
end
else
begin
--存在数据库就判断文件是否存在
declare @num int --申明一个接受返回值的变量
EXEC xp_fileexist @device ,@num output -- 执行文件存在否的验证 存在返回1 不存在返回0
if(@num = 1) --如果存在就执行还原
begin
--begin tran tDeal
--begin try

exec ('alter database '+@dbname+' set offline WITH ROLLBACK IMMEDIATE;')

select @sql='RESTORE DATABASE @db_name FROM DISK=@filename with '
select @sql=@sql +' replace'
select @par='@db_name nvarchar(128),@filename nvarchar(260)'
execute sp_executesql @sql,@par,@db_name=@dbname,@filename=@device

exec ('alter database '+@dbname+' set online with rollback IMMEDIATE;')
--删除备份文件（这句可以去掉）
--set @cmd = 'del ' +  @device
--exec master..xp_cmdshell @cmd
--end try
--begin catch
--rollback tran tDeal
--return 0
--end catch
end
end