【IT168 技术文档】
方法一
一般情况下，SQL数据库的收缩并不能很大程度上减小数据库大小，其主要作用是收缩日志大小，应当定期进行此操作以免数据库日志过大
1、设置数据库模式为简单模式：打开SQL企业管理器，在控制台根目录中依次点开Microsoft SQL Server-->SQL Server组-->双击打开你的服务器-->双击打开数据库目录-->选择你的数据库名称(如论坛数据库Forum)-->然后点击右键选择属性-->选择选项-->在故障还原的模式中选择“简单”，然后按确定保存
2、在当前数据库上点右键，看所有任务中的收缩数据库，一般里面的默认设置不用调整，直接点确定
3、收缩数据库完成后，建议将您的数据库属性重新设置为标准模式，操作方法同第一点，因为日志在一些异常情况下往往是恢复数据库的重要依据
方法二
SET NOCOUNT ON
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT
USE tablename -- 要操作的数据库名
SELECT @LogicalFileName = ’tablename_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
WHLE ((@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
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT
USE tablename -- 要操作的数据库名
SELECT @LogicalFileName = ’tablename_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
WHLE ((@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
