代碼
/*********************
求1+2+3+4+......................+100的和*******************************/
declare @sum smallint,@i smallint
set @i=1
set @sum=0
label:
if (@i<=100)
begin
set @sum=@sum+@i
set @i=@i+1
goto label
end
print @sum
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都說不要用goto,可我看了一些經典sql 代碼,也是常用goto的呀?大家如何看待goto呢?
(轉自:http://topic.csdn.net/t/20060324/22/4638629.html)
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都說不要用goto,可我看了一些經典sql 代碼,也是常用goto的呀?大家如何看待goto呢?
大多用到出錯時的跳轉,可是想問問大家,如果不用goto,用什麼辦法實現這個功能呢?
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goto不是功能不好,而是會使得代碼混亂,可讀性差。一般改用IF等判斷語句
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我還是覺得最好不用!!
怕用成習慣!!
一多起來!跳到什麼地方去了都不知道!(個人意見!!)
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另外一個例子:
代碼
USE [spb2.3]
GO
/****** 對象: StoredProcedure [dbo].[spb_WidgetInstances_UserInitialize] 指令碼日期: 01/18/2010 15:55:00 ******/
SET ANSI_NULLS OFF
GO
SET QUOTED_IDENTIFIER OFF
GO
CREATE procedure [dbo].[spb_WidgetInstances_UserInitialize]
(
@OwnerID int,
@PageCode char(4),
@Theme nvarchar(32)
)
as
SET Transaction Isolation Level Read UNCOMMITTED
SET NOCOUNT ON
if (@OwnerID<>0)
begin
Begin transaction
delete from spb_LayoutPages where OwnerID=@OwnerID and PageCode=@PageCode and Theme=@Theme
if(@@error<>0) goto Failure
delete from spb_WidgetsInZones where OwnerID=@OwnerID and ZoneID in
(select ZoneID from spb_WidgetZones where PageCode=@PageCode and Theme=@Theme)
if(@@error<>0) goto Failure
insert into spb_WidgetsInZones (WidgetID,OwnerID,ZoneID,WidgetXml,DisplayOrder)
(select W.WidgetID,@OwnerID,W.ZoneID,W.WidgetXml,W.DisplayOrder from spb_WidgetsInZones W with (nolock) inner join spb_WidgetZones Z with (nolock)
on W.ZoneID = Z.ZoneID where W.OwnerID=0 and Z.PageCode=@PageCode and Z.Theme=@Theme)
if(@@error<>0) goto Failure
commit transaction
return
Failure:
rollback transaction
return
end