#!/usr/bin/perl -w
use Data::Dumper;

my $data = '/Data/Table1.txt'; 
open INFILE, '<', $data or die "aa\n";

my %hash = map { chomp; split /\t/ } <INFILE>;
print Dumper(\%hash);

my $data2 = '/Data/Table2.txt'; 
open INFILE2, '<', $data2 or die "aa\n";

my %hash2;
while(<INFILE2>)
{
   chomp;
   my $line = $_;
   
   my $key = (split/\t/, $line)[0];
   push @{ $hash2{$key} }, $line;
}

print Dumper(\%hash2);