main_script:
============
use strict;
use warnings;
...
...
use lib '/home/hosting/foo.bar/public_html/libs/perl';
use OpenSubtitles::Help;

...
( $i->{FileName} ) = $dbh->selectrow_array(qq{
  select SubFileName
  from subs_subtitle_file a
  left join subs_subtitle b on a.SubtitleID = b.IDSubtitle
  where IDSubtitleFile = ?
}, {}, $i->{IDSubtitleFile});

module_script:
==============
package OpenSubtitles::Help;
use strict;
use warnings;
use vars qw(@ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $VERSION);

use Exporter;
use DBI;

$VERSION = 1.00;
@ISA = ('Exporter');
@EXPORT = qw(   $dbh
                get_user
);

#db connect
our $dbh = DBI->connect("DBI:mysql:database=sub;host=localhost;port=3306",
"foo", "bar",
{
        AutoCommit => 1,
        RaiseError => 1,
}) or die "Can't connect: ", $DBI::errstr;

...
1;