SQL Server 2008 R2 下如何清理数据库日志文件

USE [master]  
GO  
ALTER DATABASE [数据库名] SET RECOVERY SIMPLE WITH NO_WAIT  
GO  
ALTER DATABASE [数据库名] SET RECOVERY SIMPLE  
GO  
USE [数据库名]  
GO  
DBCC SHRINKFILE (N'[数据库日志文件名称]' , 0,TRUNCATEONLY)  
GO  
USE [master]  
GO  
ALTER DATABASE [数据库名] SET RECOVERY FULL WITH NO_WAIT  
GO  
ALTER DATABASE [数据库名] SET RECOVERY FULL  
GO  
  
--查询指定数据库的日志文件名称  
USE [数据库名]   
GO  
SELECT name FROM SYS.database_files WHERE type_desc='LOG'