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set @strSQL = 'select count(*) as Total from [' 
+ @tblName + '] where 1=1 '+ @strWhere

 

2、收缩数据库

--重建索引
DBCC REINDEX
DBCC INDEXDEFRAG
--收缩数据和日志
DBCC SHRINKDB
DBCC SHRINKFILE

 

3、压缩数据库

dbcc shrinkdatabase(dbname)

 

4、转移数据库给新用户以已存在用户权限

exec sp_change_users_login 'update_one','newname','oldname'
go

 

5、检查备份集

RESTORE VERIFYONLY from disk='E:\dvbbs.bak'

 

6、修复数据库

ALTER DATABASE [dvbbs] SET SINGLE_USER
GO
DBCC CHECKDB('dvbbs',repair_allow_data_loss) WITH TABLOCK
GO
ALTER DATABASE [dvbbs] SET MULTI_USER
GO

 

7、日志清除

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
 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

 

8、更改某个表

exec sp_changeobjectowner 'tablename','dbo'

 

9、存储更改全部表

CREATE PROCEDURE dbo.User_ChangeObjectOwnerBatch
@OldOwner as NVARCHAR(128),
@NewOwner as NVARCHAR(128)
AS

DECLARE @Name    as NVARCHAR(128)
DECLARE @Owner as NVARCHAR(128)
DECLARE @OwnerName as NVARCHAR(128)

DECLARE curObject CURSOR FOR 
select 'Name'    = name,
   'Owner'    = user_name(uid)
from sysobjects
where user_name(uid)=@OldOwner
order by name

OPEN   curObject
FETCH NEXT FROM curObject INTO @Name, @Owner
WHILE(@@FETCH_STATUS=0)
BEGIN     
if @Owner=@OldOwner
begin
   set @OwnerName = @OldOwner + '.' + rtrim(@Name)
   exec sp_changeobjectowner @OwnerName, @NewOwner
end
-- select @name,@NewOwner,@OldOwner

FETCH NEXT FROM curObject INTO @Name, @Owner
END

close curObject
deallocate curObject
GO

 

10、SQL SERVER中直接循环写入数据

declare @i int
set @i=1
while @i<30
begin
    insert into test (userid) values(@i)
    set @i=@i+1
end

案例:有如下表,要求就裱中所有沒有及格的成績,在每次增長0.1的基礎上,使他們剛好及格:

 

while((select min(score) from tb_table)<60)
begin
update tb_table set score =score*1.01
where score<60
if  (select min(score) from tb_table)>60
  break
 else
    continue
end


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