PROCEDURE pr_check_image_validality
IS
ln_instep                    PLS_INTEGER;
lt_delete_time               a.image_add_time%type;
ld_image_add_time            a.image_add_time%type;
lv_file_id                   a.file_id%type;
cursor lc_create_date
is select image_add_time,file_id,add_months(image_add_time,6) from a;
BEGIN
    ln_instep := 1;
    open lc_create_date;
    loop
         fetch lc_create_date into ld_image_add_time,lv_image_guid,lt_delete_time;
         exit when lc_create_date%notfound;
         ln_instep := 2;
         if trunc(to_number(substr((lt_delete_time-ld_image_add_time),1,instr(lt_delete_time-ld_image_add_time,' ')))) > 180 then
              delete from a
              where file_id = lv_file_id;
         end if;
    end loop;
    commit;
EXCEPTION
    when others then
         raise_application_error (-20999,'Error : abc.pr_check_image_validality (' || ln_instep ||') '|| sqlcode || sqlerrm);
END pr_check_image_validality;