MYSQL数据库触发器的插入限制[急]

MYSQL没有TRIGGER回滚 create trigger update_exceed BEFORE INSERT on A for each row begin select count(*) into @ee from A where UserID=new.UserID; if @ee>=5 then insert into A(id) values(0); end if; end 加粗部分,就是拦截部分。由于MYSQL在触发器内不允许对