有关日志压缩

[日期：2005-07-08]来源：CSDN  作者：[字体：大中小]
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS OFF
GO
CREATE PROCEDURE strink_logspace
AS
SET NOCOUNT ON
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT
SELECT  @LogicalFileName = rtrim(name),
@MaxMinutes = 10,      -- 最大执行时间
@NewSize    = 10       -- 最小空间
from sysfiles where status & 0x40 = 0x40
-- Setup / initialize
DECLARE @OriginalSize int
SELECT @OriginalSize = size -- in 8K pages
FROM sysfiles
WHERE name = @LogicalFileName
SELECT db_name() +‘日志原始大小‘ +
CONVERT(VARCHAR(30),@OriginalSize) + ‘ pages/ 8K 或 ‘ +
CONVERT(VARCHAR(30),(@OriginalSize*8/1024)) + ‘MB‘
FROM sysfiles
WHERE name = @LogicalFileName
CREATE TABLE DummyTrans
(DummyColumn char (8000) not null)
-- Wrap log and truncate it.
DECLARE @Counter   INT,
@StartTime DATETIME,
@TruncLog  VARCHAR(255)
SELECT  @StartTime = GETDATE(),
@TruncLog = ‘BACKUP LOG [‘+ db_name() + ‘] WITH TRUNCATE_ONLY‘
-- Try an initial shrink.
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)  -- the log has not shrunk
AND (@OriginalSize * 8 /1024) > @NewSize  -- The value passed in for new size is smaller than the current size.
BEGIN -- Outer loop.
SELECT @Counter = 0
WHILE  ((@Counter < @OriginalSize / 16) AND (@Counter < 50000))
BEGIN -- update
INSERT DummyTrans VALUES (‘Fill Log‘)  -- Because it is a char field it inserts 8000 bytes.
DELETE DummyTrans
SELECT @Counter = @Counter + 1
END   -- update
EXEC (@TruncLog)  -- See if a trunc of the log shrinks it.
END   -- outer loop
DBCC SHRINKFILE (@LogicalFileName, @NewSize)
SELECT db_name() +‘日志最后大小‘ +
CONVERT(VARCHAR(30),size) + ‘ pages/ 8K 或  ‘ +
CONVERT(VARCHAR(30),(size*8/1024)) + ‘MB‘
FROM sysfiles
WHERE name = @LogicalFileName
DROP TABLE DummyTrans
PRINT ‘*** 数据库日志压缩成功 ***‘
SET NOCOUNT OFF
GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO
--used
exec strink_logspace