if (! $Global::var{'dbh'}) {

    my $sdn  = "DBI:mysql:database=$db;host=$host";
    my $dbh  = DBI->connect($sdn, $user, $pass) || die ("Unable to connect to DB: $DBI::errstr");
    $Global::var{'dbh'} = $dbh;
}
return ($Global::var{'dbh'});