"read only" query

Question

Hi folks
Trying to solve a problem with my cousin's eMac (which I am not particularly familiar with). I suggested he try starting up in Singe User Mode and running the repair command (sbin/fsck -f) but when he attempted this, he told me that his machine told him that it was "read only"
I therefore wondered if this was something specifically related to the eMac, or whether it's due to his particular set-up of the machine and whether there is something which needs adjusting to allow him to run this single user command
FYI as much as I've encouraged him to upgrade to OS X 10.4 , coming from the "if it ain't broke, don't fix it" school of thought, he's been afraid to do so and is therefore still running OS X 10.3.9 on his eMac
As always my utmost thanks in advance in the hope that you might be able to shed some light on my query
Warm regards
Bernard

Answer 1

Not sure if I understand your requirements but perhaps;
SQL> with t as (
   select 5 c1,5 c2,5 c3,5 c4 from dual union all
   select 5, 5, 5, null from dual union all
   select null, null, null, null from dual union all
   select null, null, 5, 5 from dual)
select
   nvl2(c1,1,0) +
   nvl2(c2,1,0) +
   nvl2(c3,1,0) +
   nvl2(c4,1,0) tot
from t
       TOT
         4
         3
         0
         2