UC知道如何使用触发器把更新的表记录更新回来
来源：百度知道 编辑：UC知道 时间：2024/06/16 20:49:55
create or replace trigger trg_pty_empee
before update of EMPEE_PWD on crmshare.tb_pty_empee
for each row
when (old.empee_id in ('1','21','274250'))
declare
-- local variables here
begin
if (:new.EMPEE_PWD is null or :new.EMPEE_PWD <> :old.EMPEE_PWD) then
:new.EMPEE_PWD := :old.EMPEE_PWD;
end if;
end;
before update of EMPEE_PWD on crmshare.tb_pty_empee
for each row
when (old.empee_id in ('1','21','274250'))
declare
-- local variables here
begin
if (:new.EMPEE_PWD is null or :new.EMPEE_PWD <> :old.EMPEE_PWD) then
:new.EMPEE_PWD := :old.EMPEE_PWD;
end if;
end;
例如你有一个BigClass表跟一个PermanentAssets表,PermanentAssets表中的Psort列外建引用了BigClass表中的Bname列
如果BigClass列中的Bname值被更改，那么PermanentAssets表中的Psort列值也随之更改
create trigger tr_bigclass on bigclass for update
as
if(update(Bname))
update PermanentAssets set Psort=b.Bname from PermanentAssets a,inserted b,deleted c
where Psort=c.Bname
这是为什么呢？更新啦，还要更新回来，最简单的方法就是做个触发器在看到update语句的时候不做任何操作就可以啦，