各位大侠请教:我在SQLServer中建立一张表后设定一个主键同时也是标志列id identity(1,1) primary key,我在编程的过程中向数据库中插入N多条记录后标志列是从1按顺序往下排的,但是当我从记录中间删除记录的时候,被删除的列的标志列就空在那里,下次插入数据的时候就不会再用那个 被删除的记录的标志号了,比如我原来记录标志列是1,2,3,4,5我现在删除记录3,表中记录就变成1,2,4,5,我再向表中插入数据时3这个标志位就不再用了[color=#FF0000]怎么样才能让标志位重新整理,变成1,2,3,4这样的顺序?[/color]因为我编代码的时候要用到标志列,这个 问题有 点纠结请各位伸出援手帮帮小弟吧!!!
万分感激!!!
万分感激!!!
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[ttt]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[ttt]
GO/****** Object: Table [dbo].[ttt] Script Date: 2008-12-15 17:11:26 ******/
CREATE TABLE [dbo].[ttt] (
[id] [int] IDENTITY (1, 1) NOT NULL ,
[name] [varchar] (50) COLLATE Chinese_PRC_CI_AS NULL ,
[time] [datetime] NULL
) ON [PRIMARY]
GOALTER TABLE [dbo].[ttt] ADD
CONSTRAINT [PK_ttt] PRIMARY KEY CLUSTERED
(
[id]
) ON [PRIMARY]
GOinsert into ttt(name,time) values('logan',getdate());
insert into ttt(name,time) values('peter',getdate());
insert into ttt(name,time) values('man',getdate());
insert into ttt(name,time) values('lida',getdate());
insert into ttt(name,time) values('fcuandy',getdate());select * from ttt
/*
1 logan 2008-12-15 17:36:37.780
2 peter 2008-12-15 17:36:37.780
3 man 2008-12-15 17:36:37.780
4 lida 2008-12-15 17:36:37.780
5 fcuandy 2008-12-15 17:36:37.793
*/
GO
CREATE TRIGGER tr ON ttt
INSTEAD OF INSERT
AS
SET IDENTITY_INSERT ttt ON
DECLARE @n INT
SELECT @n=MAX(id) FROM ttt
;WITH fc AS
(
SELECT n=1
UNION ALL
SELECT nn=n+1 FROM fc WHERE n<@n
),fc1 AS
(
SELECT n FROM fc a
LEFT JOIN ttt b
ON a.n = b.id
WHERE b.id IS NULL
)
INSERT ttt(id,name,time) SELECT n,name,time
FROM
(SELECT ROW_NUMBER() OVER (ORDER BY GETDATE()) idx,n FROM fc1) a
INNER JOIN
(
SELECT idx=ROW_NUMBER() OVER (ORDER BY GETDATE()),name,time FROM inserted
) b
ON a.idx=b.idx
DECLARE @r INT
SELECT @r=@@ROWCOUNT
SET IDENTITY_INSERT ttt OFF
INSERT ttt(name,time) SELECT name,time FROM
(
SELECT idx=ROW_NUMBER() OVER (ORDER BY GETDATE()),name,time FROM inserted
) x
WHERE idx>@r
GO
DELETE FROM ttt WHERE name = 'peter' OR name='lida'
GO
INSERT ttt SELECT 'xxx',getdate()
INSERT ttt SELECT 'yyy',GETDATE()
GO
SELECT * FROM ttt
/*
1 logan 2008-12-15 17:37:20.967
2 xxx 2008-12-15 17:37:21.013
3 man 2008-12-15 17:37:20.967
4 yyy 2008-12-15 17:37:21.030
5 fcuandy 2008-12-15 17:37:20.967
*/DELETE FROM ttt WHERE name ='xxx' OR name='yyy'INSERT ttt SELECT 'roy_88',GETDATE() UNION ALL SELECT 'limpire',GETDATE() UNION ALL SELECT '熊',GETDATE()SELECT * FROM ttt/*
1 logan 2008-12-15 17:38:29.450
2 roy_88 2008-12-15 17:38:29.530
3 man 2008-12-15 17:38:29.467
4 limpire 2008-12-15 17:38:29.530
5 fcuandy 2008-12-15 17:38:29.467
6 熊 2008-12-15 17:38:29.530
*/
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