怎样缩小SQL Server数据库日志文件

11/4/2007来源:SQL技巧人气:8009

  本文将向大家讲解一下怎样缩小 SQL Server 的数据库日志文件,比较简单,一看就能明白。

  问:我的数据库实际大小为600MB,日志文件实际大小为33MB,但日志文件占用空间为2.8GB!我曾经试了几种方式,SHIRNK DATABASE,TRUNCATE LOG FILE, 都没办法将文件缩小。

  答:你可以把下面的代码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。

以下是引用片段:
  -----
  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