I just wanted to comment on that "Wait some time and the execution plan will get back to normal" is not a workaround for a busy server because the accumulated full table scan process will render the server irresponsible, and eventually crash the server.
I just wanted to comment on that "Wait some time and the execution plan will get back to normal" is not a workaround for a busy server because the accumulated full table scan process will render the server irresponsible, and eventually crash the server.