package database_mod;
use DBI;

our $dbh;

sub connect {
    $dbh->### DBI connect
}#sub

sub add_user {
    $dbh->### DBI SQL, ETC
}#sub

sub report {
    $dbh->### ETC
}#sub

##</code><code>##

use database_mod;

database_mod::connect();

database_mod::add_user();

### etc

##</code><code>##

package database_mod;
use DBI;

our $dbh;

sub connect {
    $dbh->### DBI connect
}#sub

package database_user;
sub add_user {
    $database_mod::dbh->### DBI SQL, ETC
}#sub

package database_report;
sub report {
    $database_mod::dbh->### ETC
}#sub

##</code><code>##

use database_mod;
use database_user;

database_mod::connect();

database_user::add_user();

### etc

##</code><code>##

package database_mod;
use DBI;

sub new {
    ### $class, $self, bless n all.
}#sub

sub connect {
    $self->### DBI connect
}#sub


package database_user;

use base database_mod;

sub add_user {
    $self->### DBI SQL, ETC
}#sub


package database_report;

use base database_mod;

sub report {
    $database_mod::dbh->### ETC
}#sub

##</code><code>##

use database_mod;
use database_user;

my $db = new database_mod;
$db->connect();

$db->add_user();

$db->report();

### etc