小编Par*_*vez的帖子

create or replace trigger t1 
  before update of price on book 
declare 
  vdif number; 
begin 
  vdif:=:new.price-:old.price; 
  dbms_output.put_line('Price Diff is '||vdif); 
end;

我收到这个错误:

表级触发器中不允许使用新引用或旧引用