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MS SQL資料庫Log檔過大,處理方法

先確認資料庫的邏輯名稱 Select * from sys.database_files 後續以Northwind為例說明: SET NOCOUNT ON
   DECLARE @LogicalFileName sysname,
           @MaxMinutes INT,
           @NewSize INT

   -- *** MAKE SURE TO CHANGE THE NEXT 4 LINES WITH YOUR CRITERIA. ***
   USE    Northwind              -- This is the name of the database
                                 -- for which the log will be shrunk.
   SELECT  @LogicalFileName = 'Northwind_Log',  -- Use sp_helpfile to
      -- identify the logical file
      -- name that you want to shrink.
           @MaxMinutes = 10,      -- Limit on time allowed to wrap log.
           @NewSize    = 10       -- in MB

   -- Setup / initialize
   DECLARE @OriginalSize int
   SELECT @OriginalSize = size -- in 8K pages
     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)

   -- 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
   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
   PRINT '*** Perform a full database backup ***'
   SET NOCOUNT OFF

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