sub new()
{
    my $class = shift;
    my $self  = {};
    $self->{'database'} = "dbi:Sybase:database=$config{'DB_NAME'};server=$config{'DB_SERVER'};hostname=$config{'DB_HOST'};port=$config{'DB_PORT'}";
    $self->{'username'} = $config{'DB_USERNAME'};
    $self->{'password'} = $config{'DB_PASSWORD'};
     bless ( $self , $class );
    $self->{'dbh'} = $self->connect();
    return $self;
}

sub DESTROY {
	my $self = shift;
	if ( $self->{'dbh'} )
	{
		$self->close();
	}
}

sub connect()
{
	my $self = shift;
	my $dbh = DBI->connect( $self->{'database'}, $self->{'username'}, $self->{'password'} );
	if ( !defined( $dbh ) )
	{
          ...
	}
	else
	{
		return $dbh;
	}
}

sub close()
{
	my $self = shift;
	my $dbh  = shift || $self->{'dbh'};
	unless ( $dbh->disconnect() )
	{
		warn "DB disconnect failed: \$DBI::err=$DBI::err, \$DBI::errstr=$DBI::errstr";
	}
}