select cast(SUM(A2.total_mb)/1024 as decimal(7,2)) as "GB_Backup_WinNT" from
nodes A1, auditocc A2 where A1.node_name=A2.node_name AND
A1.platform_name='WinNT'

This is another interesting one.
select stgpool_name as "Storage Pool Name         ", -
   cast(sum(est_capacity_MB*pct_utilized/100/1024) as decimal(7,3)) as
"Total GB in Pool", -
   cast(count(volume_name) as decimal(4,0)) as "Tapes " -
   from volumes -
   where stgpool_name like 'CPY%' -
      or stgpool_name like 'TAPE%' -
   group by stgpool_name

Storage Pool Name              Total GB in Pool     Tapes
--------------------------     ----------------     ------
CPY_DAY_NAPWIN                          391.495          7
CPY_DAY_NAPWIN                          391.495          7
CPY_DAY_NNSAIX                          274.055          6
CPY_DAY_NNSEXCH                         950.556         15
CPY_DAY_NNSLINUX_S390                     5.632          1