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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.sparql.algebra.optimize;
import java.util.ArrayList ;
import java.util.List ;
import org.apache.jena.graph.Node ;
import org.apache.jena.graph.NodeFactory ;
import org.apache.jena.query.* ;
import org.apache.jena.rdf.model.ModelFactory ;
import org.apache.jena.sparql.algebra.Algebra ;
import org.apache.jena.sparql.algebra.Op ;
import org.apache.jena.sparql.algebra.OpVars ;
import org.apache.jena.sparql.core.DatasetGraph ;
import org.apache.jena.sparql.core.Quad ;
import org.apache.jena.sparql.core.Var ;
import org.apache.jena.sparql.engine.QueryIterator ;
import org.apache.jena.sparql.engine.ResultSetStream ;
import org.apache.jena.sparql.engine.binding.BindingFactory ;
import org.apache.jena.sparql.engine.main.QueryEngineMain ;
import org.apache.jena.sparql.resultset.ResultSetCompare ;
import org.apache.jena.sparql.resultset.TextOutput ;
import org.apache.jena.sparql.serializer.SerializationContext ;
import org.apache.jena.sparql.sse.SSE ;
import org.apache.jena.sparql.util.Symbol ;
import org.junit.AfterClass ;
import org.junit.Assert ;
import org.junit.BeforeClass ;
import org.junit.Test ;
/**
* Tests for verifying that a query returns the same results both with and
* without a given optimizer enabled
*
*/
public class TestSemanticEquivalence {
private static Dataset implJoin;
@BeforeClass
public static void setup() {
// Dataset for implicit join tests
implJoin = DatasetFactory.createTxnMem();
Node a = NodeFactory.createURI("http://a");
Node b = NodeFactory.createURI("http://b");
Node c = NodeFactory.createURI("http://c");
Node p1 = NodeFactory.createURI("http://p1");
Node p2 = NodeFactory.createURI("http://p2");
Node pSelf = NodeFactory.createURI("http://self");
Node o = NodeFactory.createLiteral("object");
DatasetGraph dsg = implJoin.asDatasetGraph();
dsg.add(Quad.defaultGraphNodeGenerated, a, p1, o);
dsg.add(Quad.defaultGraphNodeGenerated, a, p2, o);
dsg.add(Quad.defaultGraphNodeGenerated, b, p1, o);
dsg.add(Quad.defaultGraphNodeGenerated, b, p2, o);
dsg.add(Quad.defaultGraphNodeGenerated, c, p1, o);
//dsg.add(Quad.defaultGraphNodeGenerated, a, pSelf, a);
// Currently these optimizations are off by default
Assert.assertFalse(ARQ.isFalse(ARQ.optFilterImplicitJoin));
Assert.assertFalse(ARQ.isFalse(ARQ.optImplicitLeftJoin));
}
@AfterClass
public static void teardown() {
if (implJoin != null) {
implJoin.close();
implJoin = null;
}
// Currently these optimizations are off by default
Assert.assertFalse(ARQ.isFalse(ARQ.optFilterImplicitJoin));
Assert.assertFalse(ARQ.isFalse(ARQ.optImplicitLeftJoin));
}
@Test
public void implicitJoinEvaluation1() {
String query = "SELECT * WHERE { ?x <http://p1> ?o1 . ?y <http://p2> ?o2 . FILTER(?x = ?y) }";
test(query, implJoin, ARQ.optFilterImplicitJoin, 2);
String alg1 = "(filter (= ?x ?y) (bgp (?x <http://p1> ?o1)(?y <http://p2> ?o2)))";
testAsAlgebra(alg1, implJoin, ARQ.optFilterImplicitJoin, 2);
String alg2 = "(filter (= ?y ?x) (bgp (?x <http://p1> ?o1)(?y <http://p2> ?o2)))";
testAsAlgebra(alg2, implJoin, ARQ.optFilterImplicitJoin, 2);
}
@Test
public void implicitJoinEvaluation2() {
String query = "SELECT * WHERE { ?x <http://p1> ?o1 . ?y <http://noSuchPredicate> ?o2 . FILTER(?x = ?y) }";
test(query, implJoin, ARQ.optFilterImplicitJoin, 0);
String alg1 = "(filter (= ?x ?y) (bgp (?x <http://p1> ?o1)(?y <http://noSuchPredicate> ?o2)))";
testAsAlgebra(alg1, implJoin, ARQ.optFilterImplicitJoin, 0);
String alg2 = "(filter (= ?y ?x) (bgp (?x <http://p1> ?o1)(?y <http://noSuchPredicate> ?o2)))";
testAsAlgebra(alg1, implJoin, ARQ.optFilterImplicitJoin, 0);
}
@Test
public void implicitJoinEvaluation3() {
String query = "SELECT * WHERE { ?x <http://p1> ?o1 . FILTER(?x = ?y) }";
test(query, implJoin, ARQ.optFilterImplicitJoin, 0);
String alg1 = "(filter (= ?x ?y) (bgp (?x <http://p1> ?o1)))";
testAsAlgebra(alg1, implJoin, ARQ.optFilterImplicitJoin, 0);
String alg2 = "(filter (= ?y ?x) (bgp (?x <http://p1> ?o1)))";
testAsAlgebra(alg1, implJoin, ARQ.optFilterImplicitJoin, 0);
}
@Test
public void implicitLeftJoinEvaluation1() {
String query = "SELECT * WHERE { ?x <http://p1> ?o1 . OPTIONAL { ?y <http://p2> ?o2 . FILTER(?x = ?y) } }";
test(query, implJoin, ARQ.optImplicitLeftJoin, 3);
String alg1 = "(leftjoin (bgp (?x <http://p1> ?o1)) (bgp (?y <http://p2> ?o2)) (= ?x ?y))";
testAsAlgebra(alg1, implJoin, ARQ.optImplicitLeftJoin, 3);
String alg2 = "(leftjoin (bgp (?x <http://p1> ?o1)) (bgp (?y <http://p2> ?o2)) (= ?y ?x))";
testAsAlgebra(alg2, implJoin, ARQ.optImplicitLeftJoin, 3);
}
@Test
public void implicitLeftJoinEvaluation2() {
String query = "SELECT * WHERE { ?x <http://p1> ?o1 . OPTIONAL { ?y <http://p2> ?o2 . FILTER(?x = ?y && ?o1 >= ?o2) } }";
test(query, implJoin, ARQ.optImplicitLeftJoin, 3);
String alg1 = "(leftjoin (bgp (?x <http://p1> ?o1)) (bgp (?y <http://p2> ?o2)) (&& (= ?x ?y)(> ?o1 ?o2)))";
testAsAlgebra(alg1, implJoin, ARQ.optImplicitLeftJoin, 3);
String alg2 = "(leftjoin (bgp (?x <http://p1> ?o1)) (bgp (?y <http://p2> ?o2)) (&& (= ?y ?x)(> ?o1 ?o2)))";
testAsAlgebra(alg2, implJoin, ARQ.optImplicitLeftJoin, 3);
}
@Test
public void implicitLeftJoinEvaluation3() {
String query = "SELECT * WHERE { ?x ?p ?o . OPTIONAL { ?y ?p1 ?o1 . ?y ?p2 ?z . FILTER(?x = ?y) FILTER(?x = ?z) FILTER(?y = ?z) } }";
test(query, implJoin, ARQ.optImplicitLeftJoin, 5);
String alg1 = "(leftjoin (bgp (?x ?p ?o)) (bgp (?y ?p1 ?o1) (?y ?p2 ?z)) ((= ?x ?y) (= ?x ?z) (= ?y ?z)))";
testAsAlgebra(alg1, implJoin, ARQ.optImplicitLeftJoin, 5);
}
/**
* Tests whether a query gives the same results when run both with and
* without a given optimizer
*
* @param queryStr
* Query
* @param ds
* Dataset
* @param opt
* Optimizer
* @param expected
* Expected number of results
*/
public static void test(String queryStr, Dataset ds, Symbol opt, int expected) {
Query q = QueryFactory.create(queryStr);
if (!q.isSelectType())
Assert.fail("Only SELECT queries are testable with this method");
Op op = Algebra.compile(q);
// Track current state
boolean isEnabled = ARQ.isTrue(opt);
boolean isDisabled = ARQ.isFalse(opt);
try {
// Run first without optimization
ARQ.set(opt, false);
ResultSetRewindable rs ;
try(QueryExecution qe = QueryExecutionFactory.create(q, ds)) {
rs = ResultSetFactory.makeRewindable(qe.execSelect());
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());
}
// Run with optimization
ARQ.set(opt, true);
ResultSetRewindable rsOpt ;
try(QueryExecution qeOpt = QueryExecutionFactory.create(q, ds)) {
rsOpt = ResultSetFactory.makeRewindable(qeOpt.execSelect());
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());
}
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);
}
}
}
/**
* 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);
}
}
}
}