缩小数据库日志的另类方法代码分析
2024-07-21 02:35:31
供稿：网友
SET NOCOUNT ON
DECLARE @LOGICALFILENAME SYSNAME,
@MAXMINUTES INT,
@NEWSIZE INT
USE abc---要操作的数据库
SELECT @LOGICALFILENAME = 'abc_LOG',---日志文件名
@MAXMINUTES = 10,---LIMIT ON TIME ALLOWED TO WRAP LOG.
@NEWSIZE = 1---你想设定的日志文件大小(M)
--SETUP /INITIALIZE
DECLARE @ORIGINALSIZE INT
SELECT @ORIGINALSIZE = SIZE
FROM SYSFILES
WHERE NAME = @LOGICALFILENAME
SELECT 原日志大小='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 @COUNT 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 NOE EXPIRED
AND @ORIGINALSIZE =(SELECT SIZE FROM SYSFILES WHERE NAME = @LOGICALFILENAME)
AND (@ORIGINALSIZE*8/1024)>@NEWSIZE
BEGIN --OUTER LOOP.
SELECT @COUNT = 0
WHILE((@COUNT<@ORIGINALSIZE/16) AND (@COUNT<50000))
BEGIN -- UPDATE
INSERT DUMMYTRANS VALUES ('FILL LOG')
DELETE DUMMYTRANS
SELECT @COUNT = @COUNT + 1
END
EXEC (@TRUNCLOG)
END
SELECT 新日志大小='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
