vr = subnoderelation;
vr = subnoderelation.makeClone ();
    public Relation getVirtualSubnodeRelation () {	if (!virtual)	    throw new RuntimeException ("getVirtualSubnodeRelation called on non-virtual relation");	Relation vr = null;	if (subnoderelation != null)	    vr = subnoderelation;	else	    vr = new Relation (other, localField, remoteField, direction, subnodesAreProperties);	vr.groupby = groupby;	vr.groupbyorder = groupbyorder;	vr.groupbyprototype = groupbyprototype;	vr.order = order;	vr.subnoderelation = subnoderelation;	return vr;    }