sub new
{
   my ( $class ) = @_;
                                                                                
   if (! defined $UsageDB::_instance )
   {
      $UsageDB::_instance = $class->_init();
   }
                                                                                
   return $UsageDB::_instance;
}
                                                                                
sub _init
{
   my ( $class ) = @_;
                                                                                
   my $self = bless {}, $class;
                                                                                
   # get configuration for connection

   $self->{_handle} = DBI->connect($dsn,$user,$pass, {PrintError => 1,
                                                      RaiseError => 1});
   return $self;
}
                                                                                
=item handle
                                                                                
Return the connected DBI handle to the usage DB
                                                                                
                                                                                
=cut
                                                                                
sub handle
{
   my ( $self ) = @_;
                                                                                
   return $self->{_handle};
}