“where 1=1” 是表示选择全部    “where 1=2”全部不选，

如：if @strWhere !='' 

begin

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

end

else 

begin

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

end

我们可以直接写成

错误！未找到目录项。

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

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

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 curObjectGO

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:

       Name     score

       Zhangshan     80

       Lishi       59

       Wangwu      50

       Songquan      69

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

 

本文转自 charles_wang888 51CTO博客，原文链接：http://blog.51cto.com/supercharles888/840137，如需转载请自行联系原作者