也谈如何缩小SQL SERVER日志文件

2022-07-15 80酷酷网 80kuku.com

　　server

前几天也碰到日志文件过大的问题，数据库实际大小为600M, 日志文件实际大小为33M, 但日志文件占用空间为2.8G!!!
试了多种方式，SHIRNK DATABASE， TRUNCATE LOG FILE, 都没办法将文件缩小。无论如何，这应该算SQL SERVER的一个BUG吧。

后来找到下面的代码，就可以将日志文件缩小到自己想要的大小了。把代码COPY到查询分析器里，，然后修改其中的3个参数(数据库名，日志文件名，和目标日志文件的大小)，运行即可(我已经用过多次了)
-----
SET NOCOUNT ON
DECLARE LogicalFileName sysname,
MaxMinutes INT,
NewSize INT

USE     Marias             -- 要操作的数据库名
SELECT LogicalFileName = 'Marias_log', -- 日志文件名
MaxMinutes = 10,               -- Limit on time allowed to wrap log.
        NewSize = 100                  -- 你想设定的日志文件的大小(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