sqlite触发器问题 no such table:main.old

                             sqlite触发器问题 no such table:main.old

CREATE TRIGGER [getUpdate] AFTER UPDATE On [tbContent] FOR EACH ROW
begin
select * from old;
end;
官方不是说可以用old,new之类的吗，为什么我执行update语句时触发的getUpdate报错: no such table: main.old