QUERY NEED FOR TIME DIFFERENCE

Hi
I need a query to find the difference between time
for example
5.00 hours - 0.30 minutes = 4.30 hours
Thanks in Advance
Adina

Is this what you are looking for -
1  select to_date('05:00', 'hh24:mi') - 0.5/24   --Subtract ½ Hr from time
  2* from dual
SQL> /
TO_DATE('05:
200804010430
  1  select to_date('05:00', 'hh24:mi') - 3/24     --Subtract 3 Hrs from time
  2* from dual
SQL> /
TO_DATE('05:
200804010200
  1  select to_date('05:30', 'hh24:mi') + 0.5/24   --Adds ½ Hr to the time
  2* from dual
SQL> /
TO_DATE('05:
200804010600
  1  select to_date('20080416 00:02', 'yyyymmdd hh24:mi') - 0.5/24     --Subtract ½ Hr from time  2* from dual
SQL> /
TO_DATE('200
200804152332Shailender Mehta

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    So I guess that means I should be looking at a 1TB drive for my iMac which currently has ~250GB of data on it. Time to review that Bare Feats 1TB drive shootout (http://www.barefeats.com/hard94.html).

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