try {
// Run first without optimization
ARQ.set(opt, false);
QueryEngineMain engine = new QueryEngineMain(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
QueryIterator iter = engine.eval(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
ResultSetRewindable rs = ResultSetFactory.makeRewindable(new ResultSetStream(vars, ModelFactory.createDefaultModel(),
iter));
if (expected != rs.size()) {
System.err.println("Non-optimized results not as expected");
TextOutput output = new TextOutput((SerializationContext)null);