select id = identity(int,1,1) , * into b from a update b set 字段2 = 10 where id = 1 update b set 字段2 = 5 where id <> 1delete from a insert into a(字段1,字段2) select 字段1,字段2 from bdrop table b
if object_id('pubs..a') is not null drop table a gocreate table a(字段1 varchar(10),字段2 int) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) goselect id = identity(int,1,1) , * into b from a update b set 字段2 = 10 where id = 1 update b set 字段2 = 5 where id <> 1delete from a insert into a(字段1,字段2) select 字段1,字段2 from bselect * from adrop table a,b/* 字段1 字段2 ---------- ----------- a 10 a 5 a 5 a 5 a 5(所影响的行数为 5 行)*/
create table a(字段1 varchar(10),字段2 int) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0) insert into a(字段1,字段2) values('a',0)用 alter table a add id int identity(1,1) not null再更新最后 alter table a drop column id--删新增列
update b
set 字段2 = 10 where id = 1
update b
set 字段2 = 5 where id <> 1delete from a
insert into a(字段1,字段2) select 字段1,字段2 from bdrop table b
drop table a
gocreate table a(字段1 varchar(10),字段2 int)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
goselect id = identity(int,1,1) , * into b from a
update b
set 字段2 = 10 where id = 1
update b
set 字段2 = 5 where id <> 1delete from a
insert into a(字段1,字段2) select 字段1,字段2 from bselect * from adrop table a,b/*
字段1 字段2
---------- -----------
a 10
a 5
a 5
a 5
a 5(所影响的行数为 5 行)*/
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)
insert into a(字段1,字段2) values('a',0)用
alter table a add id int identity(1,1) not null再更新最后
alter table a drop column id--删新增列