You could use HASHES OF ARRAYS: 
use strict;
use warnings;
use Data::Dumper;

my %hoa;
while (<DATA>) {
    my ($name, $num) = split;
    push @{$hoa{$name}}, $num;
}
print Dumper(\%hoa);

__DATA__
DAVID 31
DAVID 29
DAVID 41

[download]

prints: 

$VAR1 = {
          'DAVID' => [
                       '31',
                       '29',
                       '41'
                     ]
        };

[download]

In reply to Re: Howto deal with multiple Hash key values by toolic
in thread Multiple Hash key values problem !! by ashnator

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