如何返回比请求的行数更多的精确提取

Question

我的过程可以编译，但是，我得到一个错误提示

  

完全提取返回的行数超过了请求的行数

我不确定如何解决此问题。这是我得到的错误

01422. 00000 - "exact fetch returns more than requested number of rows"
*Cause:    The number specified in exact fetch is less than the rows returned.
*Action:   Rewrite the query or change number of rows requested

这是我的代码。

create or replace type seat_list_type as varray(5) of varchar2(10);

create or replace procedure select_seat
    ( v_tid  int
    , v_seat seat_list_type )
as
    counter         number;
    v_seatselection int;
    v_quantity      int;
    v_status        int;
    v_available     int;
    v_count         int;
    v_sid           int;
begin
    -- Check whether transaction id is valid
    select count(tid) into counter from transaction where tid = v_tid;

    if counter < 1 then
        dbms_output.put_line('Transaction ID is not valid');
    else
        select seat_selection into v_seatselection
        from   transaction t
             , showtime    st
        where  t.show_id = st.show_id;

        if v_seatselection < 1 then
            dbms_output.put_line('This showtime has no seat selection');
        else
            select quantity into v_quantity
            from   transaction
            where  tid = v_tid;

            dbms_output.put_line('size is the same');

            if v_quantity <> v_seat.count then
                dbms_output.put_line('Size no match');
            else
                v_available := 1;

                for i in 1 .. v_seat.count loop
                    -- Check for v_seat(i), the ith selected seat, whether it is available,
                    -- this can be done by an implicit cursor with select count(*)
                    select count(*) into v_count
                    from   seat -- (the table storing status of seats)
                    where  s_status = 1;

                    if v_count = 0 then
                        dbms_output.put_line('seat ' || v_seat(i) || ' is not available');
                        -- if one seat is not available, change the flag.
                        v_available := 0;
                        exit;
                    end if;
                end loop;

                if v_available = 1 then
                    -- update each selected seat's status
                    update ticket
                    set    sid = v_seat
                    where  ticket_id =
                           ( select ticket_id
                             from   ticket_purchase
                             where  tid = v_tid
                             and    sid is null );
                end if;

            end if;
        end if;
    end if;
end;