I avoided *RelWriterImpl.**checkInputsPresentInExplain* by overriding
*AbstractRelNode.computeDigest*.
Thanks,
Gelbana
On Mon, Mar 12, 2018 at 10:02 PM, Muhammad Gelbana <m.gelb...@gmail.com>
wrote:
> I'm trying to push down projections while querying a DB but I'm facing
> the below exception. I've written the following code based on my
> understanding of the Druid adapter as it seems to be analogous to what I
> need to achieve.
>
> *Projection pushdown rule*
>
>> import static com.google.common.collect.ImmutableList.of;
>> import static java.util.Arrays.asList;
>> import static org.apache.calcite.util.Util.last;
>>
>> public class SQLiProjectionRule extends RelOptRule {
>>
>> public SQLiProjectionRule() {
>> super(operand(LogicalProject.class, operand(SQLiQuery.class,
>> any())), "ProjectionRule");
>> }
>>
>> @Override
>> public Convention getOutConvention() {
>> return BindableConvention.INSTANCE;
>> }
>>
>> @Override
>> public void onMatch(RelOptRuleCall call) {
>> SQLiQuery query = call.rel(1);
>>
>> LogicalProject project = call.rel(0);
>> RelNode newProject = project.copy(project.getTraitSet(),
>> of(last(query.getInputs())));
>>
>> SQLiQuery newNode = (SQLiQuery) query.copy(project.
>> getTraitSet().replace(getOutConvention()), asList(newProject));
>>
>> call.transformTo(newNode);
>> }
>> }
>>
>
>
> *SQLiQuery portions*
>>
>> @Override
>> protected RelDataType deriveRowType() {
>> List<RelDataTypeField> topMostRelFieldList =
>> Util.last(inputs).getRowType().getFieldList();
>> return
>> getCluster().getTypeFactory().createStructType(Util.right(topMostRelFieldList),
>> Util.left(topMostRelFieldList));
>> }
>>
>> @Override
>> public RelNode copy(RelTraitSet traitSet, List<RelNode> extraInputs) {
>> List<RelNode> copiedInputs = new ArrayList<>();
>> if (this.inputs != null) copiedInputs.addAll(this.inputs);
>> if (extraInputs != null) copiedInputs.addAll(extraInputs);
>> return new SQLiQuery(getTable(), this.sqliTable, this.rowType,
>> getCluster(), traitSet, copiedInputs);
>> }
>>
>
> *Stacktrace*
>
>> java.sql.SQLException: Error while executing SQL "SELECT COUNTRY_NAME
>> FROM SALES.COUNTRIES": Index: 0, Size: 0
>> at org.apache.calcite.avatica.Helper.createException(Helper.java:56)
>> at org.apache.calcite.avatica.Helper.createException(Helper.java:41)
>> at org.apache.calcite.avatica.AvaticaStatement.executeInternal(
>> AvaticaStatement.java:156)
>> at org.apache.calcite.avatica.AvaticaStatement.executeQuery(
>> AvaticaStatement.java:218)
>> at com.sqlinterface.data.provider.calcite.internal.
>> Test_SQLi.test(Test_SQLi.java:34)
>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>> at sun.reflect.NativeMethodAccessorImpl.invoke(
>> NativeMethodAccessorImpl.java:62)
>> at sun.reflect.DelegatingMethodAccessorImpl.invoke(
>> DelegatingMethodAccessorImpl.java:43)
>> at java.lang.reflect.Method.invoke(Method.java:498)
>> at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(
>> FrameworkMethod.java:50)
>> at org.junit.internal.runners.model.ReflectiveCallable.run(
>> ReflectiveCallable.java:12)
>> at org.junit.runners.model.FrameworkMethod.invokeExplosively(
>> FrameworkMethod.java:47)
>> at org.junit.internal.runners.statements.InvokeMethod.
>> evaluate(InvokeMethod.java:17)
>> at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
>> at org.junit.runners.BlockJUnit4ClassRunner.runChild(
>> BlockJUnit4ClassRunner.java:78)
>> at org.junit.runners.BlockJUnit4ClassRunner.runChild(
>> BlockJUnit4ClassRunner.java:57)
>> at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
>> at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
>> at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
>> at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
>> at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
>> at org.junit.internal.runners.statements.RunBefores.
>> evaluate(RunBefores.java:26)
>> at org.junit.internal.runners.statements.RunAfters.evaluate(
>> RunAfters.java:27)
>> at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
>> at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(
>> JUnit4TestReference.java:86)
>> at org.eclipse.jdt.internal.junit.runner.TestExecution.
>> run(TestExecution.java:38)
>> at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.
>> runTests(RemoteTestRunner.java:459)
>> at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.
>> runTests(RemoteTestRunner.java:678)
>> at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.
>> run(RemoteTestRunner.java:382)
>> at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.
>> main(RemoteTestRunner.java:192)
>> *Caused by: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0*
>> at java.util.ArrayList.rangeCheck(ArrayList.java:657)
>> at java.util.ArrayList.get(ArrayList.java:433)
>> at org.apache.calcite.rel.externalize.RelWriterImpl.
>> checkInputsPresentInExplain(RelWriterImpl.java:167)
>> at org.apache.calcite.rel.externalize.RelWriterImpl.
>> done(RelWriterImpl.java:152)
>> at org.apache.calcite.rel.AbstractRelNode.explain(
>> AbstractRelNode.java:314)
>> at org.apache.calcite.rel.AbstractRelNode.computeDigest(
>> AbstractRelNode.java:422)
>> at org.apache.calcite.rel.AbstractRelNode.recomputeDigest(
>> AbstractRelNode.java:358)
>> at org.apache.calcite.plan.hep.HepPlanner.updateVertex(
>> HepPlanner.java:842)
>> at org.apache.calcite.plan.hep.HepPlanner.addRelToGraph(
>> HepPlanner.java:782)
>> at org.apache.calcite.plan.hep.HepPlanner.addRelToGraph(
>> HepPlanner.java:758)
>> at org.apache.calcite.plan.hep.HepPlanner.setRoot(HepPlanner.
>> java:150)
>> at org.apache.calcite.tools.Programs$2.run(Programs.java:212)
>> at org.apache.calcite.tools.Programs$SequenceProgram.run(
>> Programs.java:387)
>> at org.apache.calcite.prepare.Prepare.optimize(Prepare.java:188)
>> at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:319)
>> at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:230)
>> at org.apache.calcite.prepare.CalcitePrepareImpl.prepare2_(
>> CalcitePrepareImpl.java:781)
>> at org.apache.calcite.prepare.CalcitePrepareImpl.prepare_(
>> CalcitePrepareImpl.java:640)
>> at org.apache.calcite.prepare.CalcitePrepareImpl.prepareSql(
>> CalcitePrepareImpl.java:610)
>> at org.apache.calcite.jdbc.CalciteConnectionImpl.parseQuery(
>> CalciteConnectionImpl.java:221)
>> at org.apache.calcite.jdbc.CalciteMetaImpl.prepareAndExecute(
>> CalciteMetaImpl.java:603)
>> at org.apache.calcite.avatica.AvaticaConnection.
>> prepareAndExecuteInternal(AvaticaConnection.java:638)
>> at org.apache.calcite.avatica.AvaticaStatement.executeInternal(
>> AvaticaStatement.java:149)
>> ... 27 more
>>
>
> The exception occurs in this method because *values.size() == 0*
>
>> private boolean checkInputsPresentInExplain(RelNode node) {
>> int i = 0;
>> if (values.size() > 0 && values.get(0).left.equals("subset")) {
>> ++i;
>> }
>> for (RelNode input : node.getInputs()) {
>> assert values.get(i).right == input; *// Exception thrown here*
>> ++i;
>> }
>> return true;
>> }
>>
>
> Please tell me if I need to provide more information.
>
> Thanks,
> Gelbana
>
