触发器无效
create or replace trigger tr_card
before insert or update
on USERS for each row
begin
update USERS set card_id ='AN'||to_char(sysdate,'yyyy-mm-dd-hh24:mi:ss')||CARD_ID where users.id_users=:new.id_users;
end;
想在每次插入时修改users表的ID,可是不知道为什么触发器不报错,但是无效