You'd probably be better off if you had stored your times using your database's native date/time format (instead of munging with integer col's). But in short: 
  my $tdiff = ($hour1 - $hour2) * 60 + ($min1 - $min2);
  my $diff_hour = int(tdiff / 60);
  my $diff_min = $tdiff % 60;

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In reply to Re: Totaling Time by lhoward
in thread Totaling Time by nlafferty

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