use constant LOGIN 	=> 'name';
use constant PASS 	=> 'pwd';
use constant IP 	=> '190.xxx.xxx.xx';
use constant DB_NAME 	=> 'mydbname';

##</code><code>##

package constant;
use Exporter ();
@ISA = qw (Exporter);
@EXPORT_OK = qw ( LOGIN PASS IP  DB_NAME);
use constant LOGIN 	=> 'name';
use constant PASS 	=> 'pwd';
use constant IP 	=> '190.xxx.xxx.xx';
use constant DB_NAME 	=> 'mydbname';
1;

##</code><code>##

use constant;
@ISA = qw (constant);
...

DBI->connect ("DBI:mysql:host=".IP.";database=".DB_NAME."", LOGIN, PASS,{PrintError => 0, RaiseError => 1})