untested (it seems your rows are already sorted): 
my $last_date;
for my $row (@rows) {
  if ($row->{start_date} ne $last_date) {
    print "$row->{start_date}\n";
    $last_date = $row->{start_date};
  }
  printf "%8s %8s", $row->{id_number}, $row->{start_time};
}

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In reply to Re: help formatting output of particular loop by tinita
in thread help formatting output of particular loop by eisdrache

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