declare
	type TRecData is record(
		n1	number,
		n2	number
	);
	type TTabData is table of TRecData;
	va_data	TTabData;
	rc_data	sys_refcursor;
begin
	open rc_data for
		select	level,
				case
					when mod(level, 20) = 0 then 20
				end
		from	dual c
		connect by level <= 1035
	;
	if rc_data%isopen then
		loop
			fetch rc_data bulk collect into va_data limit 1000;
			if va_data.count > 0 then
				for j in va_data.first .. va_data.last loop
					if va_data(j).n2 is null then
						va_data.delete(j);
					end if;
					--dbms_output.put_line(j);
				end loop;
			end if;
			exit when rc_data%notfound;
		end loop;
		close rc_data;
	end if;
end;