MSSQL×ÔÔöÁÐÖØ複與²»連續
--> Title : ×ÔÔöÁÐÖØ複與²»連續
--> Author : wufeng4552
--> Date : 2009-11-13 08:31:12
--×ÔÔöÁÐͨ³£ÔÚÒÔÏÂ幾種Çé況¶ø導Ö²»連續
if object_id('tb')is not null drop table tb
go
create table tb(ID int identity(0,1),name varchar(10)unique)
--1²åÈëʧ敗×Ô動»Ø滾
insert tb([name]) select 'A'
insert tb([name]) select 'A'
/*
錯誤ÔÒò
訊Ï¢2627£¬層級14£¬狀態1£¬ÐÐ4
違·´UNIQUE KEY 條¼þ約Êø'UQ__tb__6B79F03D'¡£無·¨ÔÚÎï¼þ'dbo.tb' ÖвåÈëÖØ複µÄË÷Òý鍵¡£
陳ÊöʽÒÑ經結Êø¡£
*/
insert tb([name]) select 'B'
select * from tb
-->²é詢結¹û
/*
(1 個資ÁÏÁÐÊܵ½Ó°響)
ID name
----------- ----------
0 A
2 B
(2 個資ÁÏÁÐÊܵ½Ó°響)
*/
if object_id('tb')is not null drop table tb
go
create table tb(ID int identity(0,1),name varchar(10)unique)
--2ÊÖ動»Ø滾
insert tb([name]) select 'B'
begin tran
insert tb([name]) select 'A'
rollback tran
insert tb([name]) select 'C'
select * from tb
-->²é詢結¹û
/*
ID name
----------- ----------
0 B
2 C
(2 個資ÁÏÁÐÊܵ½Ó°響)
*/
if object_id('tb')is not null drop table tb
go
create table tb(ID int identity(0,1),name varchar(10)unique)
--3ÖØÖÃ種×Ó
insert tb([name]) select 'B'
dbcc checkident(tb,reseed,2)
insert tb([name]) select 'C'
insert tb([name]) select 'D'
select * from tb
-->²é詢結¹û
/*
ID name
-----------
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