USE [master]
GO
ALTER DATABASE AFMS SET RECOVERY SIMPLE WITH NO_WAIT
GO
ALTER DATABASE AFMS SET RECOVERY SIMPLE
GO
USE AFMS
GO
DBCC SHRINKFILE (N'AFMS_Log' , 11, TRUNCATEONLY) 
GO
USE [master]
GO
ALTER DATABASE AFMS SET RECOVERY FULL WITH NO_WAIT
GO
ALTER DATABASE AFMS SET RECOVERY FULL
GO

USE [master]
GO
ALTER DATABASE DNName SET RECOVERY SIMPLE WITH NO_WAIT
GO
ALTER DATABASE DNName SET RECOVERY SIMPLE --简单模式
GO
USE DNName
GO
DBCC SHRINKFILE (N'DNName_Log' , 11, TRUNCATEONLY) 

GO

 '这里的DNName_Log 如果不知道在sys.database_files里是什么名字的话，可以用以下注释的语句进行查询

'USE DNName

'GO

'SELECT file_id, nameFROM sys.database_files;

'GO
USE [master]
GO
ALTER DATABASE DNName SET RECOVERY FULL WITH NO_WAIT
GO
ALTER DATABASE DNName SET RECOVERY FULL --还原为完全模式
GO

Backup Log DNName with no_log '这里的DNName是你要收缩的数据库名，自己注意修改下面的数据库名，我就不再注释了。
go
dump transaction DNName with no_log 
go
USE DNName
DBCC SHRINKFILE (2)
Go

DUMP TRANSACTION [jb51] WITH NO_LOG 
BACKUP LOG [jb51] WITH NO_LOG 
DBCC SHRINKDATABASE([jb51])