declare
     b boolean;
     c number;
begin
     select count(*) into c from tab1 where batch=:frmRec.batch
     if c>0 then
	b := show_lov('batchlov');
     end if;
end;

declare
  b boolean;
  c number := 0;
     
  cursor c_test
  is
  select 1 x
  from   tab1 
  where  batch = :frmRec.batch;
begin
  open  c_test;
  fetch c_test into c;
  close c_test;

  if c=1 then
    b := show_lov('batchlov');
  end if;
end;

declare
     b boolean;
     c number ;
begin
     select 1 into c from tab1 where batch = :frmRec.batch;
     b := show_lov('batchlov');
exception
     when no_data_found then
     null;
end;