This may be what you want. 
use strict;
use warnings;
my $label1 = 'L1';
my $label2 = 'L2';
my %hash;
@hash{'a' .. 'h'} = (
    {$label1 => 1 },
    {$label1 => 2 },
    {$label2 => 3 },
    {$label1 => 4 },
    {$label2 => 5 },
    {$label1 => 6 },
    {$label2 => 7 },
    {$label1 => 8 },
);
while ( my( $key,$subhash ) = each %hash) {
    print "$key: $subhash->{$label1}\n" if exists $subhash->{$label1};
}

[download]
OUTPUT: 
a: 1
d: 4
h: 8
b: 2
f: 6

[download]
Bill

In reply to Re^3: iterate through a hash with two keys by BillKSmith
in thread iterate through a hash with two keys by fionbarr

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