#!/usr/bin/perl
#use strict;
use warnings;
use Text::CSV;
my %datei = (
shop => 'xt_customers.csv',
wawi => 'xt_customers.txt',
neu => 'all_customers.csv',
);

sub load_cache {
my $file = shift;
my %cache;
my $csv = Text::CSV->new ( { binary => 1 , sep_char => ";" } )
or die "File not found: ".Text::CSV->error_diag ();
my $row;
open my $fh, "<:encoding(iso-8859-1)", $file or die $file." $!";
while ( $row = $csv->getline ( $fh ) and ref $row eq 'ARRAY') {
$cache{'ID'}{@$row[0]} = $cache{'Mail'}{@$row[6]} = $row;
}
return \%cache;
}

my $cache_shop = load_cache( $datei{'shop'} );
my $cache_wawi = load_cache( $datei{'wawi'} );
my $cache_neu = %{ load_cache( $datei{'shop'} ) }{'ID'};

for my $ID ( keys %{ $cache_wawi{'ID'} }) {
$cache_neu{ $ID } = $cache_wawi{'ID'}{ $ID }
if not exists $cache_shop{'ID'}{ $ID }
and not exists $cache_shop{'Mail'}{ $cache_wawi{'ID'}{$ID}[6] };
}

for my $row ( values %$cache_neu ) { print join(';', @$row[0..17])