首先,你需要建立测试数据表,一个用于插入数据:test3,另外一个作为备份:test3_bak
代码如下:create table test3(id int primary key not null
identity(1,1),uname varchar(20),uage int);
create table test3_bak(id int primary key not
null identity(1,1),bid int,uname varchar(20),
uage int,active char(1));
第二步,编写备份用的触发器,只有更新或者是插入的时候才触发
代码如下:
alter trigger test3_bak_insert_update
on test3
for insert,update
as
declare @id int
declare @uname varchar(20)
declare @uage int
begin
select @id=id,@uname=uname,@uage=uage from inserted
if @id0
begin
update test3_bak set active='0' where bid=@id
insert into test3_bak(bid,uname,uage,active)
values(@id,@uname,@uage,'1')
end
end
第三步,测试数据:
代码如下:
insert into test3(uname,uage) values('FLB',20)
insert into test3(uname,uage) values('FLB1',21)
insert into test3(uname,uage) values('FLB2',22)
update test3 set uage=100 where id=27
delete from test3 where id=20
最后,你可自己采用下面方法查询跟踪两个表的数据变化:
代码如下:
select * from test3
select * from test3_bak

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