create table test(name varchar(20),password int)
//添加自增
alter table test add id int identity(1,1)//前一个1是自增开始的数字，后一个1是自增的间隔
alter table test drop column id
select * from test
insert into test values('we',23)
insert into test values('www',233)
truncate table test
delete from test where name='we'
drop table test
在myeclipse中添加删除用id来判定该删除的id号
