username                                 date_modified
2010-nhw-es-ea-285                       2012-10-10
aab.external.audit.-.bvr.verif.externes  2012-02-22
aashee.aziz                              2012-01-27
abbas.rangwala                           2012-01-27
abbie.gardner                            2012-09-10
ab.border-frontiere                      2012-08-11
abdool.yasseen                           2012-01-31
abdullah.aboukarr                        2012-08-10
abdullahi.sheikh                         2012-02-28

##</code><code>##

fullname                                 branch
aaron.northway                           CHIEF FINANCIAL OFFICER BRANCH
aashee.aziz                              HEALTH PRODUCTS AND FOOD BRANCH
abbey.klugerman                          HEALTHY ENVIRONMENTS AND CONSUMER SAFETY BRANCH
abby.hoffman                             STRATEGIC POLICY BRANCH
abderrahim.boussanni                     CHIEF FINANCIAL OFFICER BRANCH
abdiaziz.nur                             HEALTHY ENVIRONMENTS AND CONSUMER SAFETY BRANCH
abdool.yassin                            HEALTH PRODUCTS AND FOOD BRANCH
abdoulie.manjang                         N/A
abdullah.hassen                          HEALTH PRODUCTS AND FOOD BRANCH
abdullah.patel                           REGIONS AND PROGRAMS BRANCH

##</code><code>##

username           branch                             date_modified
aashee.aziz        HEALTH PRODUCTS AND FOOD BRANCH    2012-01-27
abdool.yasseen     HEALTH PRODUCTS AND FOOD BRANCH    2012-01-31

##</code><code>##

#!F:\strawberry-perl-5.16.1.1\perl\bin\perl -w

use strict;
use warnings;
#use diagnostics;
use Text::CSV_XS

my %File1Map;
my %File2Map;

my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1, allow_whitespace => 1 });

open my $fh1, "<", "final.csv" or die "final.csv: $!";
$csv->column_names ($csv->getline ($fh1)); # Read the header line
while (my $row1 = $csv->getline_hr ($fh1)){
      my $File1Map{$row1->{username}} = $row1->{date_modified};
}

open my $fh2, "<", "HCDir.csv" or die "HCDir.csv: $!";
$csv->column_names ($csv->getline ($fh2)); # Read the header line
while (my $row2 = $csv->getline_hr ($fh2)){
      my $File2Map{$row2->{fullname}} = $row2->{branch};
}
	
$csv->eol ("\n"); # Now use it for output
open my $fh3, ">", "completed.csv" or die "completed.csv: $!";
my $oldvalue
my $newvalue
while ($fh1){
	$oldvalue = $File1Map{"$username"} = "$date_modified";
	$newvalue = $File2Map{"$fullname"} = "$branch";
    $csv->print ($fh3, [ $username, $newvalue, $oldvalue ]);
}