SELECT x, collect_set(y) FROM test.tableTwo group by x

At line 0, column 0: Expression 'y' is not being grouped
org.apache.calcite.runtime.CalciteContextException: At line 0, column 0: Expression 'y' is not being grouped
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at org.apache.calcite.runtime.Resources$ExInstWithCause.ex(Resources.java:463)
	at org.apache.calcite.sql.SqlUtil.newContextException(SqlUtil.java:835)
	at org.apache.calcite.sql.SqlUtil.newContextException(SqlUtil.java:820)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.newValidationError(SqlValidatorImpl.java:4911)
	at org.apache.calcite.sql.validate.AggChecker.visit(AggChecker.java:113)
	at org.apache.calcite.sql.validate.AggChecker.visit(AggChecker.java:40)
	at org.apache.calcite.sql.SqlIdentifier.accept(SqlIdentifier.java:317)
	at org.apache.calcite.sql.util.SqlBasicVisitor$ArgHandlerImpl.visitChild(SqlBasicVisitor.java:123)
	at org.apache.calcite.sql.SqlOperator.acceptCall(SqlOperator.java:868)
	at org.apache.calcite.sql.validate.AggChecker.visit(AggChecker.java:212)
	at org.apache.calcite.sql.validate.AggChecker.visit(AggChecker.java:40)
	at org.apache.calcite.sql.SqlCall.accept(SqlCall.java:139)
	at org.apache.calcite.sql.validate.AggregatingSelectScope.checkAggregateExpr(AggregatingSelectScope.java:228)
	at org.apache.calcite.sql.validate.AggregatingSelectScope.validateExpr(AggregatingSelectScope.java:237)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateExpr(SqlValidatorImpl.java:4206)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateSelectList(SqlValidatorImpl.java:4180)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateSelect(SqlValidatorImpl.java:3436)
	at org.apache.calcite.sql.validate.SelectNamespace.validateImpl(SelectNamespace.java:60)
	at org.apache.calcite.sql.validate.AbstractNamespace.validate(AbstractNamespace.java:84)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateNamespace(SqlValidatorImpl.java:1006)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateQuery(SqlValidatorImpl.java:966)
	at org.apache.calcite.sql.SqlSelect.validate(SqlSelect.java:216)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validateScopedExpression(SqlValidatorImpl.java:941)
	at org.apache.calcite.sql.validate.SqlValidatorImpl.validate(SqlValidatorImpl.java:648)
	at com.linkedin.coral.hive.hive2rel.HiveSqlToRelConverter.convertQuery(HiveSqlToRelConverter.java:59)
	at com.linkedin.coral.common.ToRelConverter.toRel(ToRelConverter.java:157)
	at com.linkedin.coral.common.ToRelConverter.convertSql(ToRelConverter.java:111)
	at com.linkedin.coral.hive.hive2rel.HiveToRelConverterTest.relToString(HiveToRelConverterTest.java:697)
	at com.linkedin.coral.hive.hive2rel.HiveToRelConverterTest.testCollectSetOrListFunction(HiveToRelConverterTest.java:693)
	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.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:80)
	at org.testng.internal.Invoker.invokeMethod(Invoker.java:701)
	at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:893)
	at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1218)
	at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:127)
	at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:111)
	at org.testng.TestRunner.privateRun(TestRunner.java:758)
	at org.testng.TestRunner.run(TestRunner.java:613)
	at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
	at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
	at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
	at org.testng.SuiteRunner.run(SuiteRunner.java:240)
	at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:53)
	at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:87)
	at org.testng.TestNG.runSuitesSequentially(TestNG.java:1170)
	at org.testng.TestNG.runSuitesLocally(TestNG.java:1095)
	at org.testng.TestNG.run(TestNG.java:1007)
	at org.gradle.api.internal.tasks.testing.testng.TestNGTestClassProcessor.runTests(TestNGTestClassProcessor.java:141)
	at org.gradle.api.internal.tasks.testing.testng.TestNGTestClassProcessor.stop(TestNGTestClassProcessor.java:90)
	at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:61)
	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.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
	at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
	at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94)
	at com.sun.proxy.$Proxy2.stop(Unknown Source)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker.stop(TestWorker.java:133)
	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.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
	at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:182)
	at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:164)
	at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:414)
	at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
	at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
	at java.lang.Thread.run(Thread.java:750)