問:如何用觸發器對SQL Server數據庫進行數據備份?
答:首先,你需要建立測試數據表,一個用於插入數據:test3,另外一個作為備份:test3_bak
以下是引用片段:
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,編寫備份用的觸發器,只有更新或者是插入的時候才觸發
以下是引用片段:
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 @id<>0
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,測試數據:
下面是引用的片段:
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
最後,你可自己采用下面的查詢蹤兩個表的數據變化:
以下是引用片段:
select * from test3
select * from test3_bak