Here is an example that might be helpful. There is no sorting during the hash traversal, but you should be able to pick out what you need with some simple sorts here and there. 
#!/usr/bin/perl

use strict;

my %students = ();

$students{456234567} = {
  name => 'Bob Smith',
  major => 'Engineering',
  level => 'Graduate',
  classes => {
    COMP8769 => {
      teacher => 'Dr.Smith',
      time => 'MWF 10:00',
      grade => 'A' },
    COMP7960 => {
      teacher => 'Dr.Smith',
      time => 'MWF 11:00',
      grade => 'B' },
    COMP7100 => {
      teacher => 'Dr. Rose',
      time => 'MWF 1:00',
      grade => 'B' },
    COMP7600 => {
      teacher => 'Dr. Gillian',
      time => 'MWF 9:00',
      grade => 'A' }}};

$students{852234567} = {
  name => 'Ivan Milla',
  major => 'Business',
  level => 'Undergrad',
  classes => {
    BUS4000 => {
      teacher => 'Dr. Rossa',
      time => 'M 2:00',
      grade => 'C' }}};

$students{123234567} = {
  name => 'Sergio Veara',
  major => 'Arts',
  level => 'Graduate' };

$students{987234567} = {
  name => 'Richard Thompson',
  major => 'Economics',
  level => 'Undergrad',
  classes => {
    ECON6900 => {
      teacher => 'Dr. Jones',
      time => 'W 9:00',
      grade => 'A' }}};

$students{963434567} = {
  name => 'Patrick Klivert',
  major => 'Economics',
  level => 'Graduate' };

$students{789234567} = {
  name => 'Janfranco Vialli',
  major => 'Engineering',
  level => 'Graduate',
  classes => {
    BUS4000 => {
      teacher => 'Dr. Rossa',
      time => 'M 2:00',
      grade => 'A' }}};

# this will display the values of the hash

foreach my $key (sort keys %students) {
  print "\n$key\n";
  foreach my $kee (keys %{ $students{$key} }) {
    print "  $kee : ";

    if (ref($students{$key}{$kee}) eq 'HASH') {
      foreach my $kei (keys %{ $students{$key}{$kee} }) {
        print "\n    $kei : ";   

        foreach my $kea (keys %{ $students{$key}{$kee}{$kei} }) {  
          print "\n      $kea : $students{$key}{$kee}{$kei}{$kea}";
        }
      }
    }
    else {
      print "$students{$key}{$kee}\n";  
    }
  }
}

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In reply to Re: Complex Data structures and sorting by Super Monkey
in thread Complex Data structures and sorting by data67

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