$experiment{'title'}='some text';
$experiment{'data'}= [data set]; 
$experiment{'test condx'}= some ref to another hash table
$experiment{'date run'}='some date';

##</code><code>##

#!/usr/bin/perl -w
use strict;

my %experiment1 = 
   ( 'title' => "some title 1",
     'data'  => [ 1, 2, 3, 4, 5, 6],
     'data2' => [10, 11, 12],
    );
    
my %experiment2 =
   (   'title' => "some title 2",
        'data'  => [ 100, 101, 103,],
        'data2' => [200, 300, 400],
        'data3' => [500, 600, 700],
    );
    
my @experimentDB = (\%experiment1, \%experiment2);

print_all_experiment_titles(\@experimentDB);
print "printing dataset(s) for all experiments\n";
print_all_data(\@experimentDB);

sub print_all_experiment_titles
{
   my $ref_LoH = shift;
   
   foreach my $href (@$ref_LoH)
   {
      print "$href->{'title'}\n";
   }
}

sub print_all_data
{
   my $ref_LoH = shift;
   
   foreach my $href (@$ref_LoH)
   {
      foreach my $key2Lref (sort grep {/data/} keys(%$href))
      {
         print "@{$href->{$key2Lref}}\n";
      }
   }
}
__END__
The above prints:
some title 1
some title 2
printing dataset(s) for all experiments
1 2 3 4 5 6
10 11 12
100 101 103
200 300 400
500 600 700