projection.addProjectionElement(subject);
projection.addProjectionElement(object);
if(graphConstraint!=null && graphConstraint.isVariable() && !graphConstraint.equals(getItem(subjectNode)) && !graphConstraint.equals(getItem(objectNode))) {
projection.addProjectionElement((Variable)graphConstraint);
}
minus.addSucceedingOperator(new OperatorIDTuple(projection,0));
return projection;
}
@Override