收缩MSSQL数据库日志的大小方法详解

BACKUP LOG 数据库名称 WITH TRUNCATE_ONLY

DBCC SHRINKDATABASE ( 数据库名称 , TRUNCATEONLY )

SET NOCOUNT ON
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT

USE tablename -- 要操作的数据库名
SELECT @LogicalFileName = 'tablename_log', -- 日志文档名
@MaxMinutes = 10, -- Limit on time allowed to wrap log.
@NewSize = 1 -- 您想设定的日志文档的大小(M)

-- Setup / initialize
DECLARE @OriginalSize int
SELECT @OriginalSize = size
FROM sysfiles
WHERE name = @LogicalFileName
SELECT 'Original Size of ' db_name() ' LOG is '
CONVERT(VARCHAR(30),@OriginalSize) ' 8K pages or '
CONVERT(VARCHAR(30),(@OriginalSize*8/1024)) 'MB'
FROM sysfiles
WHERE name = @LogicalFileName
CREATE TABLE DummyTrans
(DummyColumn char (8000) not null)

DECLARE @Counter INT,
@StartTime DATETIME,
@TruncLog VARCHAR(255)
SELECT @StartTime = GETDATE(),
@TruncLog = 'BACKUP LOG ' db_name() ' WITH TRUNCATE_ONLY'

DBCC SHRINKFILE (@LogicalFileName, @NewSize)
EXEC (@TruncLog)
-- Wrap the log if necessary.
WHILE @MaxMinutes > DATEDIFF (mi, @StartTime, GETDATE()) -- time has not expired
AND @OriginalSize = (SELECT size FROM sysfiles WHERE name = @LogicalFileName)
AND (@OriginalSize * 8 /1024) > @NewSize
BEGIN -- Outer loop.
SELECT @Counter = 0
WHILE ((@Counter < @OriginalSize / 16) AND (@Counter < 50000))
BEGIN -- update
INSERT DummyTrans VALUES ('Fill Log')
DELETE DummyTrans
SELECT @Counter = @Counter 1
END
EXEC (@TruncLog)
END
SELECT 'Final Size of ' db_name() ' LOG is '
CONVERT(VARCHAR(30),size) ' 8K pages or '
CONVERT(VARCHAR(30),(size*8/1024)) 'MB'
FROM sysfiles
WHERE name = @LogicalFileName
DROP TABLE DummyTrans
SET NOCOUNT OFF

EXEC sp_detach_db @dbname = 'pubs'

EXEC sp_attach_single_file_db @dbname = 'pubs',

@physname = 'c:/Program Files/Microsoft

SQL Server/MSSQL/Data/pubs.mdf'

EXEC sp_dboption '数据库名',

'autoshrink', 'TRUE'