/**
* Tests whether an algebra expression gives the same results when run both with and without a
* given optimizer
*
* @param algStr Algebra
* @param ds Dataset
* @param opt Optimizer
* @param expected Expected number of results
*/
public static void testAsAlgebra(String algStr, Dataset ds, Symbol opt, int expected) {
Op op = SSE.parseOp(algStr);
List<String> vars = new ArrayList<>();
for (Var v : OpVars.visibleVars(op)) {
vars.add(v.getName());
}
// Track current state
boolean isEnabled = ARQ.isTrue(opt);
boolean isDisabled = ARQ.isFalse(opt);
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);
output.format(System.out, rs);
rs.reset();
}
Assert.assertEquals(expected, rs.size());
iter.close();
// Run with optimization
ARQ.set(opt, true);
engine =
new QueryEngineMain(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
QueryIterator iterOpt =
engine.eval(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
ResultSetRewindable rsOpt =
ResultSetFactory.makeRewindable(
new ResultSetStream(vars, ModelFactory.createDefaultModel(), iterOpt));
if (expected != rsOpt.size()) {
System.err.println("Optimized results not as expected");
TextOutput output = new TextOutput((SerializationContext) null);
output.format(System.out, rsOpt);
rsOpt.reset();
}
Assert.assertEquals(expected, rsOpt.size());
iterOpt.close();
Assert.assertTrue(ResultSetCompare.isomorphic(rs, rsOpt));
} finally {
// Restore previous state
if (isEnabled) {
ARQ.set(opt, true);
} else if (isDisabled) {
ARQ.set(opt, false);
} else {
ARQ.unset(opt);
}
}
}
private void buildHashTable(QueryIterator iter1) {
state = Phase.HASH;
for (; iter1.hasNext(); ) {
Binding row1 = iter1.next();
s_countProbe++;
hashTable.put(row1);
}
iter1.close();
state = Phase.STREAM;
}
@Override
protected void closeSubIterator() {
if (JoinLib.JOIN_EXPLAIN) {
String x =
String.format(
"HashJoin: LHS=%d RHS=%d Results=%d RightMisses=%d MaxBucket=%d NoKeyBucket=%d",
s_countProbe,
s_countScan,
s_countResults,
hashTable.s_countScanMiss,
hashTable.s_maxBucketSize,
hashTable.s_noKeyBucketSize);
System.out.println(x);
}
// In case it's a peek iterator.
iterStream.close();
hashTable.clear();
}
public QueryIteratorLogging(QueryIterator input) {
super(input);
log = LoggerFactory.getLogger(input.getClass());
}
private static List<Binding> toList(QueryIterator qIter) {
List<Binding> x = new ArrayList<>();
for (; qIter.hasNext(); ) x.add(qIter.nextBinding());
return x;
}
protected Binding moveToNextBindingOrNull() {
// iterCurrent is the iterator of entries in the
// probe hashed table for the current stream row.
// iterStream is the stream of incoming rows.
switch (state) {
case DONE:
return null;
case HASH:
case INIT:
throw new IllegalStateException();
case TRAILER:
return doOneTail();
case STREAM:
}
for (; ; ) {
// Ensure we are processing a row.
while (iterCurrent == null) {
// Move on to the next row from the right.
if (!iterStream.hasNext()) {
state = Phase.TRAILER;
iterTail = joinFinished();
if (iterTail != null) return doOneTail();
return null;
}
rowStream = iterStream.next();
s_countScan++;
iterCurrent = hashTable.getCandidates(rowStream);
yielded = false;
}
// Emit one row using the rightRow and the current matched left rows.
if (!iterCurrent.hasNext()) {
iterCurrent = null;
if (!yielded) {
Binding b = noYieldedRows(rowStream);
if (b != null) {
s_countScan++;
return b;
}
}
continue;
}
// Nested loop join, only on less.
// Iterator<Binding> iter = nestedLoop(iterCurrent, rowStream) ;
Binding rowCurrentProbe = iterCurrent.next();
Binding r = Algebra.merge(rowCurrentProbe, rowStream);
Binding r2 = null;
if (r != null) r2 = yieldOneResult(rowCurrentProbe, rowStream, r);
if (r2 == null) {
// Reject
} else {
yielded = true;
s_countResults++;
return r2;
}
}
}
