What I need to do is be able to read the data based on the SECOND_NUMBER.

Sounds like you want an array of records for each value SECOND_NUMBER can take. 

my $header = <>;
chomp($header);
my @field_names = split  /\t/, $header;

my %grouped_by_num2;
while (<>) {
    chomp;
    my %rec; @rec{ @field_names } = split /\t/;
    push @{ $grouped_by_num2{$rec{SECOND_NUMBER}} }, \%rec;
}

use Data::Dumper;
print(Dumper(\%grouped_by_num2));

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In reply to Re: Which data structure should I use? by ikegami
in thread Which data structure should I use? by Anonymous Monk

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