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Posted to commits@flink.apache.org by fh...@apache.org on 2018/08/21 22:24:44 UTC

[flink] 02/03: [FLINK-10187] [table] Fix LogicalUnnestRule after upgrading to Calcite 1.17.

This is an automated email from the ASF dual-hosted git repository.

fhueske pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/flink.git

commit d8c45fa709e7c2ec7f187c81319762a83dd2d1c4
Author: Shuyi Chen <sh...@uber.com>
AuthorDate: Mon Aug 20 23:30:23 2018 -0700

    [FLINK-10187] [table] Fix LogicalUnnestRule after upgrading to Calcite 1.17.
    
    * LogicalUnnestRule needs to match correlate->...->project->uncollect
    * Remove SqlToRelConverter which was copied from Calcite to workaround CALCITE-2440.
    
    This closes #6592.
---
 .../apache/calcite/sql2rel/SqlToRelConverter.java  | 5619 --------------------
 .../plan/rules/logical/LogicalUnnestRule.scala     |   13 +
 2 files changed, 13 insertions(+), 5619 deletions(-)

diff --git a/flink-libraries/flink-table/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java b/flink-libraries/flink-table/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
deleted file mode 100644
index 564e972..0000000
--- a/flink-libraries/flink-table/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
+++ /dev/null
@@ -1,5619 +0,0 @@
-/*
- * 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.calcite.sql2rel;
-
-import org.apache.calcite.avatica.util.Spaces;
-import org.apache.calcite.linq4j.Ord;
-import org.apache.calcite.plan.Convention;
-import org.apache.calcite.plan.RelOptCluster;
-import org.apache.calcite.plan.RelOptPlanner;
-import org.apache.calcite.plan.RelOptSamplingParameters;
-import org.apache.calcite.plan.RelOptTable;
-import org.apache.calcite.plan.RelOptUtil;
-import org.apache.calcite.plan.RelTraitSet;
-import org.apache.calcite.prepare.Prepare;
-import org.apache.calcite.prepare.RelOptTableImpl;
-import org.apache.calcite.rel.RelCollation;
-import org.apache.calcite.rel.RelCollationTraitDef;
-import org.apache.calcite.rel.RelCollations;
-import org.apache.calcite.rel.RelFieldCollation;
-import org.apache.calcite.rel.RelNode;
-import org.apache.calcite.rel.RelRoot;
-import org.apache.calcite.rel.SingleRel;
-import org.apache.calcite.rel.core.AggregateCall;
-import org.apache.calcite.rel.core.Collect;
-import org.apache.calcite.rel.core.CorrelationId;
-import org.apache.calcite.rel.core.Filter;
-import org.apache.calcite.rel.core.Join;
-import org.apache.calcite.rel.core.JoinInfo;
-import org.apache.calcite.rel.core.JoinRelType;
-import org.apache.calcite.rel.core.Project;
-import org.apache.calcite.rel.core.RelFactories;
-import org.apache.calcite.rel.core.Sample;
-import org.apache.calcite.rel.core.Sort;
-import org.apache.calcite.rel.core.Uncollect;
-import org.apache.calcite.rel.core.Values;
-import org.apache.calcite.rel.logical.LogicalAggregate;
-import org.apache.calcite.rel.logical.LogicalCorrelate;
-import org.apache.calcite.rel.logical.LogicalFilter;
-import org.apache.calcite.rel.logical.LogicalIntersect;
-import org.apache.calcite.rel.logical.LogicalJoin;
-import org.apache.calcite.rel.logical.LogicalMatch;
-import org.apache.calcite.rel.logical.LogicalMinus;
-import org.apache.calcite.rel.logical.LogicalProject;
-import org.apache.calcite.rel.logical.LogicalSort;
-import org.apache.calcite.rel.logical.LogicalTableFunctionScan;
-import org.apache.calcite.rel.logical.LogicalTableModify;
-import org.apache.calcite.rel.logical.LogicalTableScan;
-import org.apache.calcite.rel.logical.LogicalUnion;
-import org.apache.calcite.rel.logical.LogicalValues;
-import org.apache.calcite.rel.metadata.JaninoRelMetadataProvider;
-import org.apache.calcite.rel.metadata.RelColumnMapping;
-import org.apache.calcite.rel.metadata.RelMetadataQuery;
-import org.apache.calcite.rel.stream.Delta;
-import org.apache.calcite.rel.stream.LogicalDelta;
-import org.apache.calcite.rel.type.RelDataType;
-import org.apache.calcite.rel.type.RelDataTypeFactory;
-import org.apache.calcite.rel.type.RelDataTypeField;
-import org.apache.calcite.rex.RexBuilder;
-import org.apache.calcite.rex.RexCall;
-import org.apache.calcite.rex.RexCallBinding;
-import org.apache.calcite.rex.RexCorrelVariable;
-import org.apache.calcite.rex.RexDynamicParam;
-import org.apache.calcite.rex.RexFieldAccess;
-import org.apache.calcite.rex.RexFieldCollation;
-import org.apache.calcite.rex.RexInputRef;
-import org.apache.calcite.rex.RexLiteral;
-import org.apache.calcite.rex.RexNode;
-import org.apache.calcite.rex.RexPatternFieldRef;
-import org.apache.calcite.rex.RexRangeRef;
-import org.apache.calcite.rex.RexShuttle;
-import org.apache.calcite.rex.RexSubQuery;
-import org.apache.calcite.rex.RexUtil;
-import org.apache.calcite.rex.RexWindowBound;
-import org.apache.calcite.schema.ColumnStrategy;
-import org.apache.calcite.schema.ModifiableTable;
-import org.apache.calcite.schema.ModifiableView;
-import org.apache.calcite.schema.Table;
-import org.apache.calcite.schema.TranslatableTable;
-import org.apache.calcite.schema.Wrapper;
-import org.apache.calcite.sql.JoinConditionType;
-import org.apache.calcite.sql.JoinType;
-import org.apache.calcite.sql.SemiJoinType;
-import org.apache.calcite.sql.SqlAggFunction;
-import org.apache.calcite.sql.SqlBasicCall;
-import org.apache.calcite.sql.SqlCall;
-import org.apache.calcite.sql.SqlCallBinding;
-import org.apache.calcite.sql.SqlDataTypeSpec;
-import org.apache.calcite.sql.SqlDelete;
-import org.apache.calcite.sql.SqlDynamicParam;
-import org.apache.calcite.sql.SqlExplainFormat;
-import org.apache.calcite.sql.SqlExplainLevel;
-import org.apache.calcite.sql.SqlFunction;
-import org.apache.calcite.sql.SqlIdentifier;
-import org.apache.calcite.sql.SqlInsert;
-import org.apache.calcite.sql.SqlIntervalQualifier;
-import org.apache.calcite.sql.SqlJoin;
-import org.apache.calcite.sql.SqlKind;
-import org.apache.calcite.sql.SqlLiteral;
-import org.apache.calcite.sql.SqlMatchRecognize;
-import org.apache.calcite.sql.SqlMerge;
-import org.apache.calcite.sql.SqlNode;
-import org.apache.calcite.sql.SqlNodeList;
-import org.apache.calcite.sql.SqlNumericLiteral;
-import org.apache.calcite.sql.SqlOperator;
-import org.apache.calcite.sql.SqlOperatorTable;
-import org.apache.calcite.sql.SqlOrderBy;
-import org.apache.calcite.sql.SqlSampleSpec;
-import org.apache.calcite.sql.SqlSelect;
-import org.apache.calcite.sql.SqlSelectKeyword;
-import org.apache.calcite.sql.SqlSetOperator;
-import org.apache.calcite.sql.SqlUnnestOperator;
-import org.apache.calcite.sql.SqlUpdate;
-import org.apache.calcite.sql.SqlUtil;
-import org.apache.calcite.sql.SqlValuesOperator;
-import org.apache.calcite.sql.SqlWindow;
-import org.apache.calcite.sql.SqlWith;
-import org.apache.calcite.sql.SqlWithItem;
-import org.apache.calcite.sql.fun.SqlCountAggFunction;
-import org.apache.calcite.sql.fun.SqlInOperator;
-import org.apache.calcite.sql.fun.SqlQuantifyOperator;
-import org.apache.calcite.sql.fun.SqlRowOperator;
-import org.apache.calcite.sql.fun.SqlStdOperatorTable;
-import org.apache.calcite.sql.parser.SqlParserPos;
-import org.apache.calcite.sql.type.SqlReturnTypeInference;
-import org.apache.calcite.sql.type.SqlTypeName;
-import org.apache.calcite.sql.type.SqlTypeUtil;
-import org.apache.calcite.sql.type.TableFunctionReturnTypeInference;
-import org.apache.calcite.sql.util.SqlBasicVisitor;
-import org.apache.calcite.sql.util.SqlVisitor;
-import org.apache.calcite.sql.validate.AggregatingSelectScope;
-import org.apache.calcite.sql.validate.CollectNamespace;
-import org.apache.calcite.sql.validate.DelegatingScope;
-import org.apache.calcite.sql.validate.ListScope;
-import org.apache.calcite.sql.validate.MatchRecognizeScope;
-import org.apache.calcite.sql.validate.ParameterScope;
-import org.apache.calcite.sql.validate.SelectScope;
-import org.apache.calcite.sql.validate.SqlMonotonicity;
-import org.apache.calcite.sql.validate.SqlNameMatcher;
-import org.apache.calcite.sql.validate.SqlQualified;
-import org.apache.calcite.sql.validate.SqlUserDefinedTableFunction;
-import org.apache.calcite.sql.validate.SqlUserDefinedTableMacro;
-import org.apache.calcite.sql.validate.SqlValidator;
-import org.apache.calcite.sql.validate.SqlValidatorImpl;
-import org.apache.calcite.sql.validate.SqlValidatorNamespace;
-import org.apache.calcite.sql.validate.SqlValidatorScope;
-import org.apache.calcite.sql.validate.SqlValidatorTable;
-import org.apache.calcite.sql.validate.SqlValidatorUtil;
-import org.apache.calcite.tools.RelBuilder;
-import org.apache.calcite.tools.RelBuilderFactory;
-import org.apache.calcite.util.ImmutableBitSet;
-import org.apache.calcite.util.ImmutableIntList;
-import org.apache.calcite.util.Litmus;
-import org.apache.calcite.util.NlsString;
-import org.apache.calcite.util.NumberUtil;
-import org.apache.calcite.util.Pair;
-import org.apache.calcite.util.Util;
-import org.apache.calcite.util.trace.CalciteTrace;
-
-import com.google.common.base.Preconditions;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableList.Builder;
-import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.Iterables;
-
-import org.slf4j.Logger;
-
-import java.lang.reflect.Type;
-import java.math.BigDecimal;
-import java.util.AbstractList;
-import java.util.ArrayDeque;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Deque;
-import java.util.EnumSet;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.LinkedHashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
-import java.util.TreeSet;
-import java.util.function.Supplier;
-
-import static org.apache.calcite.sql.SqlUtil.stripAs;
-
-/**
- * THIS FILE HAS BEEN COPIED FROM THE APACHE CALCITE PROJECT UNTIL CALCITE-2440 is fixed.
- *
- * The following IT tests will fail.
- *  - AggregateITCase.testTumbleWindowAggregateWithCollectUnnest
- *  - JoinITCase.testCrossWithUnnest
- *  - JoinITCase.testJoinWithUnnestOfTuple
- *  - SqlITCase.testLeftUnnestMultiSetFromCollectResult
- *  - SqlITCase.testUnnestArrayOfArrayFromTable
- *  - SqlITCase.testUnnestMultiSetFromCollectResult
- *  - SqlITCase.testUnnestObjectArrayFromTableWithFilter
- *  - SqlITCase.testUnnestPrimitiveArrayFromTable
- *
- * Converts a SQL parse tree (consisting of
- * {@link org.apache.calcite.sql.SqlNode} objects) into a relational algebra
- * expression (consisting of {@link org.apache.calcite.rel.RelNode} objects).
- *
- * <p>The public entry points are: {@link #convertQuery},
- * {@link #convertExpression(SqlNode)}.
- */
-public class SqlToRelConverter {
-	//~ Static fields/initializers ---------------------------------------------
-
-	protected static final Logger SQL2REL_LOGGER =
-			CalciteTrace.getSqlToRelTracer();
-
-	private static final BigDecimal TWO = BigDecimal.valueOf(2L);
-
-	/** Size of the smallest IN list that will be converted to a semijoin to a
-	 * static table. */
-	public static final int DEFAULT_IN_SUB_QUERY_THRESHOLD = 20;
-
-	@Deprecated // to be removed before 2.0
-	public static final int DEFAULT_IN_SUBQUERY_THRESHOLD =
-			DEFAULT_IN_SUB_QUERY_THRESHOLD;
-
-	//~ Instance fields --------------------------------------------------------
-
-	protected final SqlValidator validator;
-	protected final RexBuilder rexBuilder;
-	protected final Prepare.CatalogReader catalogReader;
-	protected final RelOptCluster cluster;
-	private SubQueryConverter subQueryConverter;
-	protected final List<RelNode> leaves = new ArrayList<>();
-	private final List<SqlDynamicParam> dynamicParamSqlNodes = new ArrayList<>();
-	private final SqlOperatorTable opTab;
-	protected final RelDataTypeFactory typeFactory;
-	private final SqlNodeToRexConverter exprConverter;
-	private int explainParamCount;
-	public final SqlToRelConverter.Config config;
-	private final RelBuilder relBuilder;
-
-	/**
-	 * Fields used in name resolution for correlated sub-queries.
-	 */
-	private final Map<CorrelationId, DeferredLookup> mapCorrelToDeferred =
-			new HashMap<>();
-
-	/**
-	 * Stack of names of datasets requested by the <code>
-	 * TABLE(SAMPLE(&lt;datasetName&gt;, &lt;query&gt;))</code> construct.
-	 */
-	private final Deque<String> datasetStack = new ArrayDeque<>();
-
-	/**
-	 * Mapping of non-correlated sub-queries that have been converted to their
-	 * equivalent constants. Used to avoid re-evaluating the sub-query if it's
-	 * already been evaluated.
-	 */
-	private final Map<SqlNode, RexNode> mapConvertedNonCorrSubqs =
-			new HashMap<>();
-
-	public final RelOptTable.ViewExpander viewExpander;
-
-	//~ Constructors -----------------------------------------------------------
-	/**
-	 * Creates a converter.
-	 *
-	 * @param viewExpander    Preparing statement
-	 * @param validator       Validator
-	 * @param catalogReader   Schema
-	 * @param planner         Planner
-	 * @param rexBuilder      Rex builder
-	 * @param convertletTable Expression converter
-	 */
-	@Deprecated // to be removed before 2.0
-	public SqlToRelConverter(
-			RelOptTable.ViewExpander viewExpander,
-			SqlValidator validator,
-			Prepare.CatalogReader catalogReader,
-			RelOptPlanner planner,
-			RexBuilder rexBuilder,
-			SqlRexConvertletTable convertletTable) {
-		this(viewExpander, validator, catalogReader,
-				RelOptCluster.create(planner, rexBuilder), convertletTable,
-				Config.DEFAULT);
-	}
-
-	@Deprecated // to be removed before 2.0
-	public SqlToRelConverter(
-			RelOptTable.ViewExpander viewExpander,
-			SqlValidator validator,
-			Prepare.CatalogReader catalogReader,
-			RelOptCluster cluster,
-			SqlRexConvertletTable convertletTable) {
-		this(viewExpander, validator, catalogReader, cluster, convertletTable,
-				Config.DEFAULT);
-	}
-
-	/* Creates a converter. */
-	public SqlToRelConverter(
-			RelOptTable.ViewExpander viewExpander,
-			SqlValidator validator,
-			Prepare.CatalogReader catalogReader,
-			RelOptCluster cluster,
-			SqlRexConvertletTable convertletTable,
-			Config config) {
-		this.viewExpander = viewExpander;
-		this.opTab =
-				(validator
-						== null) ? SqlStdOperatorTable.instance()
-						: validator.getOperatorTable();
-		this.validator = validator;
-		this.catalogReader = catalogReader;
-		this.subQueryConverter = new NoOpSubQueryConverter();
-		this.rexBuilder = cluster.getRexBuilder();
-		this.typeFactory = rexBuilder.getTypeFactory();
-		this.cluster = Objects.requireNonNull(cluster);
-		this.exprConverter = new SqlNodeToRexConverterImpl(convertletTable);
-		this.explainParamCount = 0;
-		this.config = new ConfigBuilder().withConfig(config).build();
-		this.relBuilder = config.getRelBuilderFactory().create(cluster, null);
-	}
-
-	//~ Methods ----------------------------------------------------------------
-
-	/**
-	 * @return the RelOptCluster in use.
-	 */
-	public RelOptCluster getCluster() {
-		return cluster;
-	}
-
-	/**
-	 * Returns the row-expression builder.
-	 */
-	public RexBuilder getRexBuilder() {
-		return rexBuilder;
-	}
-
-	/**
-	 * Returns the number of dynamic parameters encountered during translation;
-	 * this must only be called after {@link #convertQuery}.
-	 *
-	 * @return number of dynamic parameters
-	 */
-	public int getDynamicParamCount() {
-		return dynamicParamSqlNodes.size();
-	}
-
-	/**
-	 * Returns the type inferred for a dynamic parameter.
-	 *
-	 * @param index 0-based index of dynamic parameter
-	 * @return inferred type, never null
-	 */
-	public RelDataType getDynamicParamType(int index) {
-		SqlNode sqlNode = dynamicParamSqlNodes.get(index);
-		if (sqlNode == null) {
-			throw Util.needToImplement("dynamic param type inference");
-		}
-		return validator.getValidatedNodeType(sqlNode);
-	}
-
-	/**
-	 * Returns the current count of the number of dynamic parameters in an
-	 * EXPLAIN PLAN statement.
-	 *
-	 * @param increment if true, increment the count
-	 * @return the current count before the optional increment
-	 */
-	public int getDynamicParamCountInExplain(boolean increment) {
-		int retVal = explainParamCount;
-		if (increment) {
-			++explainParamCount;
-		}
-		return retVal;
-	}
-
-	/**
-	 * @return mapping of non-correlated sub-queries that have been converted to
-	 * the constants that they evaluate to
-	 */
-	public Map<SqlNode, RexNode> getMapConvertedNonCorrSubqs() {
-		return mapConvertedNonCorrSubqs;
-	}
-
-	/**
-	 * Adds to the current map of non-correlated converted sub-queries the
-	 * elements from another map that contains non-correlated sub-queries that
-	 * have been converted by another SqlToRelConverter.
-	 *
-	 * @param alreadyConvertedNonCorrSubqs the other map
-	 */
-	public void addConvertedNonCorrSubqs(
-			Map<SqlNode, RexNode> alreadyConvertedNonCorrSubqs) {
-		mapConvertedNonCorrSubqs.putAll(alreadyConvertedNonCorrSubqs);
-	}
-
-	/**
-	 * Sets a new SubQueryConverter. To have any effect, this must be called
-	 * before any convert method.
-	 *
-	 * @param converter new SubQueryConverter
-	 */
-	public void setSubQueryConverter(SubQueryConverter converter) {
-		subQueryConverter = converter;
-	}
-
-	/**
-	 * Sets the number of dynamic parameters in the current EXPLAIN PLAN
-	 * statement.
-	 *
-	 * @param explainParamCount number of dynamic parameters in the statement
-	 */
-	public void setDynamicParamCountInExplain(int explainParamCount) {
-		assert config.isExplain();
-		this.explainParamCount = explainParamCount;
-	}
-
-	private void checkConvertedType(SqlNode query, RelNode result) {
-		if (query.isA(SqlKind.DML)) {
-			return;
-		}
-		// Verify that conversion from SQL to relational algebra did
-		// not perturb any type information.  (We can't do this if the
-		// SQL statement is something like an INSERT which has no
-		// validator type information associated with its result,
-		// hence the namespace check above.)
-		final List<RelDataTypeField> validatedFields =
-				validator.getValidatedNodeType(query).getFieldList();
-		final RelDataType validatedRowType =
-				validator.getTypeFactory().createStructType(
-						Pair.right(validatedFields),
-						SqlValidatorUtil.uniquify(Pair.left(validatedFields),
-								catalogReader.nameMatcher().isCaseSensitive()));
-
-		final List<RelDataTypeField> convertedFields =
-				result.getRowType().getFieldList().subList(0, validatedFields.size());
-		final RelDataType convertedRowType =
-				validator.getTypeFactory().createStructType(convertedFields);
-
-		if (!RelOptUtil.equal("validated row type", validatedRowType,
-				"converted row type", convertedRowType, Litmus.IGNORE)) {
-			throw new AssertionError("Conversion to relational algebra failed to "
-					+ "preserve datatypes:\n"
-					+ "validated type:\n"
-					+ validatedRowType.getFullTypeString()
-					+ "\nconverted type:\n"
-					+ convertedRowType.getFullTypeString()
-					+ "\nrel:\n"
-					+ RelOptUtil.toString(result));
-		}
-	}
-
-	public RelNode flattenTypes(
-			RelNode rootRel,
-			boolean restructure) {
-		RelStructuredTypeFlattener typeFlattener =
-				new RelStructuredTypeFlattener(relBuilder,
-						rexBuilder, createToRelContext(), restructure);
-		return typeFlattener.rewrite(rootRel);
-	}
-
-	/**
-	 * If sub-query is correlated and decorrelation is enabled, performs
-	 * decorrelation.
-	 *
-	 * @param query   Query
-	 * @param rootRel Root relational expression
-	 * @return New root relational expression after decorrelation
-	 */
-	public RelNode decorrelate(SqlNode query, RelNode rootRel) {
-		if (!enableDecorrelation()) {
-			return rootRel;
-		}
-		final RelNode result = decorrelateQuery(rootRel);
-		if (result != rootRel) {
-			checkConvertedType(query, result);
-		}
-		return result;
-	}
-
-	/**
-	 * Walks over a tree of relational expressions, replacing each
-	 * {@link RelNode} with a 'slimmed down' relational expression that projects
-	 * only the fields required by its consumer.
-	 *
-	 * <p>This may make things easier for the optimizer, by removing crud that
-	 * would expand the search space, but is difficult for the optimizer itself
-	 * to do it, because optimizer rules must preserve the number and type of
-	 * fields. Hence, this transform that operates on the entire tree, similar
-	 * to the {@link RelStructuredTypeFlattener type-flattening transform}.
-	 *
-	 * <p>Currently this functionality is disabled in farrago/luciddb; the
-	 * default implementation of this method does nothing.
-	 *
-	 * @param ordered Whether the relational expression must produce results in
-	 * a particular order (typically because it has an ORDER BY at top level)
-	 * @param rootRel Relational expression that is at the root of the tree
-	 * @return Trimmed relational expression
-	 */
-	public RelNode trimUnusedFields(boolean ordered, RelNode rootRel) {
-		// Trim fields that are not used by their consumer.
-		if (isTrimUnusedFields()) {
-			final RelFieldTrimmer trimmer = newFieldTrimmer();
-			final List<RelCollation> collations =
-					rootRel.getTraitSet().getTraits(RelCollationTraitDef.INSTANCE);
-			rootRel = trimmer.trim(rootRel);
-			if (!ordered
-					&& collations != null
-					&& !collations.isEmpty()
-					&& !collations.equals(ImmutableList.of(RelCollations.EMPTY))) {
-				final RelTraitSet traitSet = rootRel.getTraitSet()
-						.replace(RelCollationTraitDef.INSTANCE, collations);
-				rootRel = rootRel.copy(traitSet, rootRel.getInputs());
-			}
-			if (SQL2REL_LOGGER.isDebugEnabled()) {
-				SQL2REL_LOGGER.debug(
-						RelOptUtil.dumpPlan("Plan after trimming unused fields", rootRel,
-								SqlExplainFormat.TEXT, SqlExplainLevel.EXPPLAN_ATTRIBUTES));
-			}
-		}
-		return rootRel;
-	}
-
-	/**
-	 * Creates a RelFieldTrimmer.
-	 *
-	 * @return Field trimmer
-	 */
-	protected RelFieldTrimmer newFieldTrimmer() {
-		return new RelFieldTrimmer(validator, relBuilder);
-	}
-
-	/**
-	 * Converts an unvalidated query's parse tree into a relational expression.
-	 *
-	 * @param query           Query to convert
-	 * @param needsValidation Whether to validate the query before converting;
-	 *                        <code>false</code> if the query has already been
-	 *                        validated.
-	 * @param top             Whether the query is top-level, say if its result
-	 *                        will become a JDBC result set; <code>false</code> if
-	 *                        the query will be part of a view.
-	 */
-	public RelRoot convertQuery(
-			SqlNode query,
-			final boolean needsValidation,
-			final boolean top) {
-		if (needsValidation) {
-			query = validator.validate(query);
-		}
-
-		RelMetadataQuery.THREAD_PROVIDERS.set(
-				JaninoRelMetadataProvider.of(cluster.getMetadataProvider()));
-		RelNode result = convertQueryRecursive(query, top, null).rel;
-		if (top) {
-			if (isStream(query)) {
-				result = new LogicalDelta(cluster, result.getTraitSet(), result);
-			}
-		}
-		RelCollation collation = RelCollations.EMPTY;
-		if (!query.isA(SqlKind.DML)) {
-			if (isOrdered(query)) {
-				collation = requiredCollation(result);
-			}
-		}
-		checkConvertedType(query, result);
-
-		if (SQL2REL_LOGGER.isDebugEnabled()) {
-			SQL2REL_LOGGER.debug(
-					RelOptUtil.dumpPlan("Plan after converting SqlNode to RelNode",
-							result, SqlExplainFormat.TEXT,
-							SqlExplainLevel.EXPPLAN_ATTRIBUTES));
-		}
-
-		final RelDataType validatedRowType = validator.getValidatedNodeType(query);
-		return RelRoot.of(result, validatedRowType, query.getKind())
-				.withCollation(collation);
-	}
-
-	private static boolean isStream(SqlNode query) {
-		return query instanceof SqlSelect
-				&& ((SqlSelect) query).isKeywordPresent(SqlSelectKeyword.STREAM);
-	}
-
-	public static boolean isOrdered(SqlNode query) {
-		switch (query.getKind()) {
-			case SELECT:
-				return ((SqlSelect) query).getOrderList() != null
-						&& ((SqlSelect) query).getOrderList().size() > 0;
-			case WITH:
-				return isOrdered(((SqlWith) query).body);
-			case ORDER_BY:
-				return ((SqlOrderBy) query).orderList.size() > 0;
-			default:
-				return false;
-		}
-	}
-
-	private RelCollation requiredCollation(RelNode r) {
-		if (r instanceof Sort) {
-			return ((Sort) r).collation;
-		}
-		if (r instanceof Project) {
-			return requiredCollation(((Project) r).getInput());
-		}
-		if (r instanceof Delta) {
-			return requiredCollation(((Delta) r).getInput());
-		}
-		throw new AssertionError();
-	}
-
-	/**
-	 * Converts a SELECT statement's parse tree into a relational expression.
-	 */
-	public RelNode convertSelect(SqlSelect select, boolean top) {
-		final SqlValidatorScope selectScope = validator.getWhereScope(select);
-		final Blackboard bb = createBlackboard(selectScope, null, top);
-		convertSelectImpl(bb, select);
-		return bb.root;
-	}
-
-	/**
-	 * Factory method for creating translation workspace.
-	 */
-	protected Blackboard createBlackboard(SqlValidatorScope scope,
-	                                      Map<String, RexNode> nameToNodeMap, boolean top) {
-		return new Blackboard(scope, nameToNodeMap, top);
-	}
-
-	/**
-	 * Implementation of {@link #convertSelect(SqlSelect, boolean)};
-	 * derived class may override.
-	 */
-	protected void convertSelectImpl(
-			final Blackboard bb,
-			SqlSelect select) {
-		convertFrom(
-				bb,
-				select.getFrom());
-		convertWhere(
-				bb,
-				select.getWhere());
-
-		final List<SqlNode> orderExprList = new ArrayList<>();
-		final List<RelFieldCollation> collationList = new ArrayList<>();
-		gatherOrderExprs(
-				bb,
-				select,
-				select.getOrderList(),
-				orderExprList,
-				collationList);
-		final RelCollation collation =
-				cluster.traitSet().canonize(RelCollations.of(collationList));
-
-		if (validator.isAggregate(select)) {
-			convertAgg(
-					bb,
-					select,
-					orderExprList);
-		} else {
-			convertSelectList(
-					bb,
-					select,
-					orderExprList);
-		}
-
-		if (select.isDistinct()) {
-			distinctify(bb, true);
-		}
-		convertOrder(
-				select, bb, collation, orderExprList, select.getOffset(),
-				select.getFetch());
-		bb.setRoot(bb.root, true);
-	}
-
-	/**
-	 * Having translated 'SELECT ... FROM ... [GROUP BY ...] [HAVING ...]', adds
-	 * a relational expression to make the results unique.
-	 *
-	 * <p>If the SELECT clause contains duplicate expressions, adds
-	 * {@link org.apache.calcite.rel.logical.LogicalProject}s so that we are
-	 * grouping on the minimal set of keys. The performance gain isn't huge, but
-	 * it is difficult to detect these duplicate expressions later.
-	 *
-	 * @param bb               Blackboard
-	 * @param checkForDupExprs Check for duplicate expressions
-	 */
-	private void distinctify(
-			Blackboard bb,
-			boolean checkForDupExprs) {
-		// Look for duplicate expressions in the project.
-		// Say we have 'select x, y, x, z'.
-		// Then dups will be {[2, 0]}
-		// and oldToNew will be {[0, 0], [1, 1], [2, 0], [3, 2]}
-		RelNode rel = bb.root;
-		if (checkForDupExprs && (rel instanceof LogicalProject)) {
-			LogicalProject project = (LogicalProject) rel;
-			final List<RexNode> projectExprs = project.getProjects();
-			final List<Integer> origins = new ArrayList<>();
-			int dupCount = 0;
-			for (int i = 0; i < projectExprs.size(); i++) {
-				int x = findExpr(projectExprs.get(i), projectExprs, i);
-				if (x >= 0) {
-					origins.add(x);
-					++dupCount;
-				} else {
-					origins.add(i);
-				}
-			}
-			if (dupCount == 0) {
-				distinctify(bb, false);
-				return;
-			}
-
-			final Map<Integer, Integer> squished = new HashMap<>();
-			final List<RelDataTypeField> fields = rel.getRowType().getFieldList();
-			final List<Pair<RexNode, String>> newProjects = new ArrayList<>();
-			for (int i = 0; i < fields.size(); i++) {
-				if (origins.get(i) == i) {
-					squished.put(i, newProjects.size());
-					newProjects.add(RexInputRef.of2(i, fields));
-				}
-			}
-			rel =
-					LogicalProject.create(rel, Pair.left(newProjects),
-							Pair.right(newProjects));
-			bb.root = rel;
-			distinctify(bb, false);
-			rel = bb.root;
-
-			// Create the expressions to reverse the mapping.
-			// Project($0, $1, $0, $2).
-			final List<Pair<RexNode, String>> undoProjects = new ArrayList<>();
-			for (int i = 0; i < fields.size(); i++) {
-				final int origin = origins.get(i);
-				RelDataTypeField field = fields.get(i);
-				undoProjects.add(
-						Pair.of(
-								(RexNode) new RexInputRef(
-										squished.get(origin), field.getType()),
-								field.getName()));
-			}
-
-			rel =
-					LogicalProject.create(rel, Pair.left(undoProjects),
-							Pair.right(undoProjects));
-			bb.setRoot(
-					rel,
-					false);
-
-			return;
-		}
-
-		// Usual case: all of the expressions in the SELECT clause are
-		// different.
-		final ImmutableBitSet groupSet =
-				ImmutableBitSet.range(rel.getRowType().getFieldCount());
-		rel = createAggregate(bb, groupSet, ImmutableList.of(groupSet),
-				ImmutableList.of());
-
-		bb.setRoot(
-				rel,
-				false);
-	}
-
-	private int findExpr(RexNode seek, List<RexNode> exprs, int count) {
-		for (int i = 0; i < count; i++) {
-			RexNode expr = exprs.get(i);
-			if (expr.toString().equals(seek.toString())) {
-				return i;
-			}
-		}
-		return -1;
-	}
-
-	/**
-	 * Converts a query's ORDER BY clause, if any.
-	 *
-	 * @param select        Query
-	 * @param bb            Blackboard
-	 * @param collation     Collation list
-	 * @param orderExprList Method populates this list with orderBy expressions
-	 *                      not present in selectList
-	 * @param offset        Expression for number of rows to discard before
-	 *                      returning first row
-	 * @param fetch         Expression for number of rows to fetch
-	 */
-	protected void convertOrder(
-			SqlSelect select,
-			Blackboard bb,
-			RelCollation collation,
-			List<SqlNode> orderExprList,
-			SqlNode offset,
-			SqlNode fetch) {
-		if (select.getOrderList() == null
-				|| select.getOrderList().getList().isEmpty()) {
-			assert collation.getFieldCollations().isEmpty();
-			if ((offset == null
-					|| (offset instanceof SqlLiteral
-					&& ((SqlLiteral) offset).bigDecimalValue().equals(BigDecimal.ZERO)))
-					&& fetch == null) {
-				return;
-			}
-		}
-
-		// Create a sorter using the previously constructed collations.
-		bb.setRoot(
-				LogicalSort.create(bb.root, collation,
-						offset == null ? null : convertExpression(offset),
-						fetch == null ? null : convertExpression(fetch)),
-				false);
-
-		// If extra expressions were added to the project list for sorting,
-		// add another project to remove them. But make the collation empty, because
-		// we can't represent the real collation.
-		//
-		// If it is the top node, use the real collation, but don't trim fields.
-		if (orderExprList.size() > 0 && !bb.top) {
-			final List<RexNode> exprs = new ArrayList<>();
-			final RelDataType rowType = bb.root.getRowType();
-			final int fieldCount =
-					rowType.getFieldCount() - orderExprList.size();
-			for (int i = 0; i < fieldCount; i++) {
-				exprs.add(rexBuilder.makeInputRef(bb.root, i));
-			}
-			bb.setRoot(
-					LogicalProject.create(bb.root, exprs,
-							rowType.getFieldNames().subList(0, fieldCount)),
-					false);
-		}
-	}
-
-	/**
-	 * Returns whether a given node contains a {@link SqlInOperator}.
-	 *
-	 * @param node a RexNode tree
-	 */
-	private static boolean containsInOperator(
-			SqlNode node) {
-		try {
-			SqlVisitor<Void> visitor =
-					new SqlBasicVisitor<Void>() {
-						public Void visit(SqlCall call) {
-							if (call.getOperator() instanceof SqlInOperator) {
-								throw new Util.FoundOne(call);
-							}
-							return super.visit(call);
-						}
-					};
-			node.accept(visitor);
-			return false;
-		} catch (Util.FoundOne e) {
-			Util.swallow(e, null);
-			return true;
-		}
-	}
-
-	/**
-	 * Push down all the NOT logical operators into any IN/NOT IN operators.
-	 *
-	 * @param scope Scope where {@code sqlNode} occurs
-	 * @param sqlNode the root node from which to look for NOT operators
-	 * @return the transformed SqlNode representation with NOT pushed down.
-	 */
-	private static SqlNode pushDownNotForIn(SqlValidatorScope scope,
-	                                        SqlNode sqlNode) {
-		if ((sqlNode instanceof SqlCall) && containsInOperator(sqlNode)) {
-			SqlCall sqlCall = (SqlCall) sqlNode;
-			if ((sqlCall.getOperator() == SqlStdOperatorTable.AND)
-					|| (sqlCall.getOperator() == SqlStdOperatorTable.OR)) {
-				SqlNode[] sqlOperands = ((SqlBasicCall) sqlCall).operands;
-				for (int i = 0; i < sqlOperands.length; i++) {
-					sqlOperands[i] = pushDownNotForIn(scope, sqlOperands[i]);
-				}
-				return reg(scope, sqlNode);
-			} else if (sqlCall.getOperator() == SqlStdOperatorTable.NOT) {
-				SqlNode childNode = sqlCall.operand(0);
-				assert childNode instanceof SqlCall;
-				SqlBasicCall childSqlCall = (SqlBasicCall) childNode;
-				if (childSqlCall.getOperator() == SqlStdOperatorTable.AND) {
-					SqlNode[] andOperands = childSqlCall.getOperands();
-					SqlNode[] orOperands = new SqlNode[andOperands.length];
-					for (int i = 0; i < orOperands.length; i++) {
-						orOperands[i] = reg(scope,
-								SqlStdOperatorTable.NOT.createCall(SqlParserPos.ZERO,
-										andOperands[i]));
-					}
-					for (int i = 0; i < orOperands.length; i++) {
-						orOperands[i] = pushDownNotForIn(scope, orOperands[i]);
-					}
-					return reg(scope,
-							SqlStdOperatorTable.OR.createCall(SqlParserPos.ZERO,
-									orOperands[0], orOperands[1]));
-				} else if (childSqlCall.getOperator() == SqlStdOperatorTable.OR) {
-					SqlNode[] orOperands = childSqlCall.getOperands();
-					SqlNode[] andOperands = new SqlNode[orOperands.length];
-					for (int i = 0; i < andOperands.length; i++) {
-						andOperands[i] = reg(scope,
-								SqlStdOperatorTable.NOT.createCall(SqlParserPos.ZERO,
-										orOperands[i]));
-					}
-					for (int i = 0; i < andOperands.length; i++) {
-						andOperands[i] = pushDownNotForIn(scope, andOperands[i]);
-					}
-					return reg(scope,
-							SqlStdOperatorTable.AND.createCall(SqlParserPos.ZERO,
-									andOperands[0], andOperands[1]));
-				} else if (childSqlCall.getOperator() == SqlStdOperatorTable.NOT) {
-					SqlNode[] notOperands = childSqlCall.getOperands();
-					assert notOperands.length == 1;
-					return pushDownNotForIn(scope, notOperands[0]);
-				} else if (childSqlCall.getOperator() instanceof SqlInOperator) {
-					SqlNode[] inOperands = childSqlCall.getOperands();
-					SqlInOperator inOp =
-							(SqlInOperator) childSqlCall.getOperator();
-					if (inOp.kind == SqlKind.NOT_IN) {
-						return reg(scope,
-								SqlStdOperatorTable.IN.createCall(SqlParserPos.ZERO,
-										inOperands[0], inOperands[1]));
-					} else {
-						return reg(scope,
-								SqlStdOperatorTable.NOT_IN.createCall(SqlParserPos.ZERO,
-										inOperands[0], inOperands[1]));
-					}
-				} else {
-					// childSqlCall is "leaf" node in a logical expression tree
-					// (only considering AND, OR, NOT)
-					return sqlNode;
-				}
-			} else {
-				// sqlNode is "leaf" node in a logical expression tree
-				// (only considering AND, OR, NOT)
-				return sqlNode;
-			}
-		} else {
-			// tree rooted at sqlNode does not contain inOperator
-			return sqlNode;
-		}
-	}
-
-	/** Registers with the validator a {@link SqlNode} that has been created
-	 * during the Sql-to-Rel process. */
-	private static SqlNode reg(SqlValidatorScope scope, SqlNode e) {
-		scope.getValidator().deriveType(scope, e);
-		return e;
-	}
-
-	/**
-	 * Converts a WHERE clause.
-	 *
-	 * @param bb    Blackboard
-	 * @param where WHERE clause, may be null
-	 */
-	private void convertWhere(
-			final Blackboard bb,
-			final SqlNode where) {
-		if (where == null) {
-			return;
-		}
-		SqlNode newWhere = pushDownNotForIn(bb.scope, where);
-		replaceSubQueries(bb, newWhere, RelOptUtil.Logic.UNKNOWN_AS_FALSE);
-		final RexNode convertedWhere = bb.convertExpression(newWhere);
-		final RexNode convertedWhere2 =
-				RexUtil.removeNullabilityCast(typeFactory, convertedWhere);
-
-		// only allocate filter if the condition is not TRUE
-		if (convertedWhere2.isAlwaysTrue()) {
-			return;
-		}
-
-		final RelFactories.FilterFactory factory =
-				RelFactories.DEFAULT_FILTER_FACTORY;
-		final RelNode filter = factory.createFilter(bb.root, convertedWhere2);
-		final RelNode r;
-		final CorrelationUse p = getCorrelationUse(bb, filter);
-		if (p != null) {
-			assert p.r instanceof Filter;
-			Filter f = (Filter) p.r;
-			r = LogicalFilter.create(f.getInput(), f.getCondition(),
-					ImmutableSet.of(p.id));
-		} else {
-			r = filter;
-		}
-
-		bb.setRoot(r, false);
-	}
-
-	private void replaceSubQueries(
-			final Blackboard bb,
-			final SqlNode expr,
-			RelOptUtil.Logic logic) {
-		findSubQueries(bb, expr, logic, false);
-		for (SubQuery node : bb.subQueryList) {
-			substituteSubQuery(bb, node);
-		}
-	}
-
-	private void substituteSubQuery(Blackboard bb, SubQuery subQuery) {
-		final RexNode expr = subQuery.expr;
-		if (expr != null) {
-			// Already done.
-			return;
-		}
-
-		final SqlBasicCall call;
-		final RelNode rel;
-		final SqlNode query;
-		final RelOptUtil.Exists converted;
-		switch (subQuery.node.getKind()) {
-			case CURSOR:
-				convertCursor(bb, subQuery);
-				return;
-
-			case MULTISET_QUERY_CONSTRUCTOR:
-			case MULTISET_VALUE_CONSTRUCTOR:
-			case ARRAY_QUERY_CONSTRUCTOR:
-				rel = convertMultisets(ImmutableList.of(subQuery.node), bb);
-				subQuery.expr = bb.register(rel, JoinRelType.INNER);
-				return;
-
-			case IN:
-			case NOT_IN:
-			case SOME:
-			case ALL:
-				call = (SqlBasicCall) subQuery.node;
-				query = call.operand(1);
-				if (!config.isExpand() && !(query instanceof SqlNodeList)) {
-					return;
-				}
-				final SqlNode leftKeyNode = call.operand(0);
-
-				final List<RexNode> leftKeys;
-				switch (leftKeyNode.getKind()) {
-					case ROW:
-						leftKeys = new ArrayList<>();
-						for (SqlNode sqlExpr : ((SqlBasicCall) leftKeyNode).getOperandList()) {
-							leftKeys.add(bb.convertExpression(sqlExpr));
-						}
-						break;
-					default:
-						leftKeys = ImmutableList.of(bb.convertExpression(leftKeyNode));
-				}
-
-				if (query instanceof SqlNodeList) {
-					SqlNodeList valueList = (SqlNodeList) query;
-					if (!containsNullLiteral(valueList)
-							&& valueList.size() < config.getInSubQueryThreshold()) {
-						// We're under the threshold, so convert to OR.
-						subQuery.expr =
-								convertInToOr(
-										bb,
-										leftKeys,
-										valueList,
-										(SqlInOperator) call.getOperator());
-						return;
-					}
-
-					// Otherwise, let convertExists translate
-					// values list into an inline table for the
-					// reference to Q below.
-				}
-
-				// Project out the search columns from the left side
-
-				// Q1:
-				// "select from emp where emp.deptno in (select col1 from T)"
-				//
-				// is converted to
-				//
-				// "select from
-				//   emp inner join (select distinct col1 from T)) q
-				//   on emp.deptno = q.col1
-				//
-				// Q2:
-				// "select from emp where emp.deptno not in (Q)"
-				//
-				// is converted to
-				//
-				// "select from
-				//   emp left outer join (select distinct col1, TRUE from T) q
-				//   on emp.deptno = q.col1
-				//   where emp.deptno <> null
-				//         and q.indicator <> TRUE"
-				//
-				final RelDataType targetRowType =
-						SqlTypeUtil.promoteToRowType(typeFactory,
-								validator.getValidatedNodeType(leftKeyNode), null);
-				final boolean notIn = call.getOperator().kind == SqlKind.NOT_IN;
-				converted =
-						convertExists(query, RelOptUtil.SubQueryType.IN, subQuery.logic,
-								notIn, targetRowType);
-				if (converted.indicator) {
-					// Generate
-					//    emp CROSS JOIN (SELECT COUNT(*) AS c,
-					//                       COUNT(deptno) AS ck FROM dept)
-					final RelDataType longType =
-							typeFactory.createSqlType(SqlTypeName.BIGINT);
-					final RelNode seek = converted.r.getInput(0); // fragile
-					final int keyCount = leftKeys.size();
-					final List<Integer> args = ImmutableIntList.range(0, keyCount);
-					LogicalAggregate aggregate =
-							LogicalAggregate.create(seek, ImmutableBitSet.of(), null,
-									ImmutableList.of(
-											AggregateCall.create(SqlStdOperatorTable.COUNT, false,
-													false, ImmutableList.of(), -1, longType, null),
-											AggregateCall.create(SqlStdOperatorTable.COUNT, false,
-													false, args, -1, longType, null)));
-					LogicalJoin join =
-							LogicalJoin.create(bb.root, aggregate, rexBuilder.makeLiteral(true),
-									ImmutableSet.of(), JoinRelType.INNER);
-					bb.setRoot(join, false);
-				}
-				final RexNode rex =
-						bb.register(converted.r,
-								converted.outerJoin ? JoinRelType.LEFT : JoinRelType.INNER,
-								leftKeys);
-
-				RelOptUtil.Logic logic = subQuery.logic;
-				switch (logic) {
-					case TRUE_FALSE_UNKNOWN:
-					case UNKNOWN_AS_TRUE:
-						if (!converted.indicator) {
-							logic = RelOptUtil.Logic.TRUE_FALSE;
-						}
-				}
-				subQuery.expr = translateIn(logic, bb.root, rex);
-				if (notIn) {
-					subQuery.expr =
-							rexBuilder.makeCall(SqlStdOperatorTable.NOT, subQuery.expr);
-				}
-				return;
-
-			case EXISTS:
-				// "select from emp where exists (select a from T)"
-				//
-				// is converted to the following if the sub-query is correlated:
-				//
-				// "select from emp left outer join (select AGG_TRUE() as indicator
-				// from T group by corr_var) q where q.indicator is true"
-				//
-				// If there is no correlation, the expression is replaced with a
-				// boolean indicating whether the sub-query returned 0 or >= 1 row.
-				call = (SqlBasicCall) subQuery.node;
-				query = call.operand(0);
-				if (!config.isExpand()) {
-					return;
-				}
-				converted = convertExists(query, RelOptUtil.SubQueryType.EXISTS,
-						subQuery.logic, true, null);
-				assert !converted.indicator;
-				if (convertNonCorrelatedSubQuery(subQuery, bb, converted.r, true)) {
-					return;
-				}
-				subQuery.expr = bb.register(converted.r, JoinRelType.LEFT);
-				return;
-
-			case SCALAR_QUERY:
-				// Convert the sub-query.  If it's non-correlated, convert it
-				// to a constant expression.
-				if (!config.isExpand()) {
-					return;
-				}
-				call = (SqlBasicCall) subQuery.node;
-				query = call.operand(0);
-				converted = convertExists(query, RelOptUtil.SubQueryType.SCALAR,
-						subQuery.logic, true, null);
-				assert !converted.indicator;
-				if (convertNonCorrelatedSubQuery(subQuery, bb, converted.r, false)) {
-					return;
-				}
-				rel = convertToSingleValueSubq(query, converted.r);
-				subQuery.expr = bb.register(rel, JoinRelType.LEFT);
-				return;
-
-			case SELECT:
-				// This is used when converting multiset queries:
-				//
-				// select * from unnest(select multiset[deptno] from emps);
-				//
-				converted = convertExists(subQuery.node, RelOptUtil.SubQueryType.SCALAR,
-						subQuery.logic, true, null);
-				assert !converted.indicator;
-				subQuery.expr = bb.register(converted.r, JoinRelType.LEFT);
-				return;
-
-			default:
-				throw new AssertionError("unexpected kind of sub-query: "
-						+ subQuery.node);
-		}
-	}
-
-	private RexNode translateIn(RelOptUtil.Logic logic, RelNode root,
-	                            final RexNode rex) {
-		switch (logic) {
-			case TRUE:
-				return rexBuilder.makeLiteral(true);
-
-			case TRUE_FALSE:
-			case UNKNOWN_AS_FALSE:
-				assert rex instanceof RexRangeRef;
-				final int fieldCount = rex.getType().getFieldCount();
-				RexNode rexNode = rexBuilder.makeFieldAccess(rex, fieldCount - 1);
-				rexNode = rexBuilder.makeCall(SqlStdOperatorTable.IS_TRUE, rexNode);
-
-				// Then append the IS NOT NULL(leftKeysForIn).
-				//
-				// RexRangeRef contains the following fields:
-				//   leftKeysForIn,
-				//   rightKeysForIn (the original sub-query select list),
-				//   nullIndicator
-				//
-				// The first two lists contain the same number of fields.
-				final int k = (fieldCount - 1) / 2;
-				for (int i = 0; i < k; i++) {
-					rexNode =
-							rexBuilder.makeCall(
-									SqlStdOperatorTable.AND,
-									rexNode,
-									rexBuilder.makeCall(
-											SqlStdOperatorTable.IS_NOT_NULL,
-											rexBuilder.makeFieldAccess(rex, i)));
-				}
-				return rexNode;
-
-			case TRUE_FALSE_UNKNOWN:
-			case UNKNOWN_AS_TRUE:
-				// select e.deptno,
-				//   case
-				//   when ct.c = 0 then false
-				//   when dt.i is not null then true
-				//   when e.deptno is null then null
-				//   when ct.ck < ct.c then null
-				//   else false
-				//   end
-				// from e
-				// cross join (select count(*) as c, count(deptno) as ck from v) as ct
-				// left join (select distinct deptno, true as i from v) as dt
-				//   on e.deptno = dt.deptno
-				final Join join = (Join) root;
-				final Project left = (Project) join.getLeft();
-				final RelNode leftLeft = ((Join) left.getInput()).getLeft();
-				final int leftLeftCount = leftLeft.getRowType().getFieldCount();
-				final RelDataType longType =
-						typeFactory.createSqlType(SqlTypeName.BIGINT);
-				final RexNode cRef = rexBuilder.makeInputRef(root, leftLeftCount);
-				final RexNode ckRef = rexBuilder.makeInputRef(root, leftLeftCount + 1);
-				final RexNode iRef =
-						rexBuilder.makeInputRef(root, root.getRowType().getFieldCount() - 1);
-
-				final RexLiteral zero =
-						rexBuilder.makeExactLiteral(BigDecimal.ZERO, longType);
-				final RexLiteral trueLiteral = rexBuilder.makeLiteral(true);
-				final RexLiteral falseLiteral = rexBuilder.makeLiteral(false);
-				final RexNode unknownLiteral =
-						rexBuilder.makeNullLiteral(trueLiteral.getType());
-
-				final ImmutableList.Builder<RexNode> args = ImmutableList.builder();
-				args.add(rexBuilder.makeCall(SqlStdOperatorTable.EQUALS, cRef, zero),
-						falseLiteral,
-						rexBuilder.makeCall(SqlStdOperatorTable.IS_NOT_NULL, iRef),
-						trueLiteral);
-				final JoinInfo joinInfo = join.analyzeCondition();
-				for (int leftKey : joinInfo.leftKeys) {
-					final RexNode kRef = rexBuilder.makeInputRef(root, leftKey);
-					args.add(rexBuilder.makeCall(SqlStdOperatorTable.IS_NULL, kRef),
-							unknownLiteral);
-				}
-				args.add(rexBuilder.makeCall(SqlStdOperatorTable.LESS_THAN, ckRef, cRef),
-						unknownLiteral,
-						falseLiteral);
-
-				return rexBuilder.makeCall(SqlStdOperatorTable.CASE, args.build());
-
-			default:
-				throw new AssertionError(logic);
-		}
-	}
-
-	private static boolean containsNullLiteral(SqlNodeList valueList) {
-		for (SqlNode node : valueList.getList()) {
-			if (node instanceof SqlLiteral) {
-				SqlLiteral lit = (SqlLiteral) node;
-				if (lit.getValue() == null) {
-					return true;
-				}
-			}
-		}
-		return false;
-	}
-
-	/**
-	 * Determines if a sub-query is non-correlated and if so, converts it to a
-	 * constant.
-	 *
-	 * @param subQuery  the call that references the sub-query
-	 * @param bb        blackboard used to convert the sub-query
-	 * @param converted RelNode tree corresponding to the sub-query
-	 * @param isExists  true if the sub-query is part of an EXISTS expression
-	 * @return Whether the sub-query can be converted to a constant
-	 */
-	private boolean convertNonCorrelatedSubQuery(
-			SubQuery subQuery,
-			Blackboard bb,
-			RelNode converted,
-			boolean isExists) {
-		SqlCall call = (SqlBasicCall) subQuery.node;
-		if (subQueryConverter.canConvertSubQuery()
-				&& isSubQueryNonCorrelated(converted, bb)) {
-			// First check if the sub-query has already been converted
-			// because it's a nested sub-query.  If so, don't re-evaluate
-			// it again.
-			RexNode constExpr = mapConvertedNonCorrSubqs.get(call);
-			if (constExpr == null) {
-				constExpr =
-						subQueryConverter.convertSubQuery(
-								call,
-								this,
-								isExists,
-								config.isExplain());
-			}
-			if (constExpr != null) {
-				subQuery.expr = constExpr;
-				mapConvertedNonCorrSubqs.put(call, constExpr);
-				return true;
-			}
-		}
-		return false;
-	}
-
-	/**
-	 * Converts the RelNode tree for a select statement to a select that
-	 * produces a single value.
-	 *
-	 * @param query the query
-	 * @param plan   the original RelNode tree corresponding to the statement
-	 * @return the converted RelNode tree
-	 */
-	public RelNode convertToSingleValueSubq(
-			SqlNode query,
-			RelNode plan) {
-		// Check whether query is guaranteed to produce a single value.
-		if (query instanceof SqlSelect) {
-			SqlSelect select = (SqlSelect) query;
-			SqlNodeList selectList = select.getSelectList();
-			SqlNodeList groupList = select.getGroup();
-
-			if ((selectList.size() == 1)
-					&& ((groupList == null) || (groupList.size() == 0))) {
-				SqlNode selectExpr = selectList.get(0);
-				if (selectExpr instanceof SqlCall) {
-					SqlCall selectExprCall = (SqlCall) selectExpr;
-					if (Util.isSingleValue(selectExprCall)) {
-						return plan;
-					}
-				}
-
-				// If there is a limit with 0 or 1,
-				// it is ensured to produce a single value
-				if (select.getFetch() != null
-						&& select.getFetch() instanceof SqlNumericLiteral) {
-					SqlNumericLiteral limitNum = (SqlNumericLiteral) select.getFetch();
-					if (((BigDecimal) limitNum.getValue()).intValue() < 2) {
-						return plan;
-					}
-				}
-			}
-		} else if (query instanceof SqlCall) {
-			// If the query is (values ...),
-			// it is necessary to look into the operands to determine
-			// whether SingleValueAgg is necessary
-			SqlCall exprCall = (SqlCall) query;
-			if (exprCall.getOperator()
-					instanceof SqlValuesOperator
-					&& Util.isSingleValue(exprCall)) {
-				return plan;
-			}
-		}
-
-		// If not, project SingleValueAgg
-		return RelOptUtil.createSingleValueAggRel(
-				cluster,
-				plan);
-	}
-
-	/**
-	 * Converts "x IN (1, 2, ...)" to "x=1 OR x=2 OR ...".
-	 *
-	 * @param leftKeys   LHS
-	 * @param valuesList RHS
-	 * @param op         The operator (IN, NOT IN, &gt; SOME, ...)
-	 * @return converted expression
-	 */
-	private RexNode convertInToOr(
-			final Blackboard bb,
-			final List<RexNode> leftKeys,
-			SqlNodeList valuesList,
-			SqlInOperator op) {
-		final List<RexNode> comparisons = new ArrayList<>();
-		for (SqlNode rightVals : valuesList) {
-			RexNode rexComparison;
-			final SqlOperator comparisonOp;
-			if (op instanceof SqlQuantifyOperator) {
-				comparisonOp = RelOptUtil.op(((SqlQuantifyOperator) op).comparisonKind,
-						SqlStdOperatorTable.EQUALS);
-			} else {
-				comparisonOp = SqlStdOperatorTable.EQUALS;
-			}
-			if (leftKeys.size() == 1) {
-				rexComparison =
-						rexBuilder.makeCall(comparisonOp,
-								leftKeys.get(0),
-								ensureSqlType(leftKeys.get(0).getType(),
-										bb.convertExpression(rightVals)));
-			} else {
-				assert rightVals instanceof SqlCall;
-				final SqlBasicCall call = (SqlBasicCall) rightVals;
-				assert (call.getOperator() instanceof SqlRowOperator)
-						&& call.operandCount() == leftKeys.size();
-				rexComparison =
-						RexUtil.composeConjunction(
-								rexBuilder,
-								Iterables.transform(
-										Pair.zip(leftKeys, call.getOperandList()),
-										pair -> rexBuilder.makeCall(comparisonOp, pair.left,
-												ensureSqlType(pair.left.getType(),
-														bb.convertExpression(pair.right)))),
-								false);
-			}
-			comparisons.add(rexComparison);
-		}
-
-		switch (op.kind) {
-			case ALL:
-				return RexUtil.composeConjunction(rexBuilder, comparisons, true);
-			case NOT_IN:
-				return rexBuilder.makeCall(SqlStdOperatorTable.NOT,
-						RexUtil.composeDisjunction(rexBuilder, comparisons, true));
-			case IN:
-			case SOME:
-				return RexUtil.composeDisjunction(rexBuilder, comparisons, true);
-			default:
-				throw new AssertionError();
-		}
-	}
-
-	/** Ensures that an expression has a given {@link SqlTypeName}, applying a
-	 * cast if necessary. If the expression already has the right type family,
-	 * returns the expression unchanged. */
-	private RexNode ensureSqlType(RelDataType type, RexNode node) {
-		if (type.getSqlTypeName() == node.getType().getSqlTypeName()
-				|| (type.getSqlTypeName() == SqlTypeName.VARCHAR
-				&& node.getType().getSqlTypeName() == SqlTypeName.CHAR)) {
-			return node;
-		}
-		return rexBuilder.ensureType(type, node, true);
-	}
-
-	/**
-	 * Gets the list size threshold under which {@link #convertInToOr} is used.
-	 * Lists of this size or greater will instead be converted to use a join
-	 * against an inline table
-	 * ({@link org.apache.calcite.rel.logical.LogicalValues}) rather than a
-	 * predicate. A threshold of 0 forces usage of an inline table in all cases; a
-	 * threshold of Integer.MAX_VALUE forces usage of OR in all cases
-	 *
-	 * @return threshold, default {@link #DEFAULT_IN_SUB_QUERY_THRESHOLD}
-	 */
-	@Deprecated // to be removed before 2.0
-	protected int getInSubqueryThreshold() {
-		return config.getInSubQueryThreshold();
-	}
-
-	/**
-	 * Converts an EXISTS or IN predicate into a join. For EXISTS, the sub-query
-	 * produces an indicator variable, and the result is a relational expression
-	 * which outer joins that indicator to the original query. After performing
-	 * the outer join, the condition will be TRUE if the EXISTS condition holds,
-	 * NULL otherwise.
-	 *
-	 * @param seek           A query, for example 'select * from emp' or
-	 *                       'values (1,2,3)' or '('Foo', 34)'.
-	 * @param subQueryType   Whether sub-query is IN, EXISTS or scalar
-	 * @param logic Whether the answer needs to be in full 3-valued logic (TRUE,
-	 *     FALSE, UNKNOWN) will be required, or whether we can accept an
-	 *     approximation (say representing UNKNOWN as FALSE)
-	 * @param notIn Whether the operation is NOT IN
-	 * @return join expression
-	 */
-	private RelOptUtil.Exists convertExists(
-			SqlNode seek,
-			RelOptUtil.SubQueryType subQueryType,
-			RelOptUtil.Logic logic,
-			boolean notIn,
-			RelDataType targetDataType) {
-		final SqlValidatorScope seekScope =
-				(seek instanceof SqlSelect)
-						? validator.getSelectScope((SqlSelect) seek)
-						: null;
-		final Blackboard seekBb = createBlackboard(seekScope, null, false);
-		RelNode seekRel = convertQueryOrInList(seekBb, seek, targetDataType);
-
-		return RelOptUtil.createExistsPlan(seekRel,
-				subQueryType, logic, notIn, relBuilder);
-	}
-
-	private RelNode convertQueryOrInList(
-			Blackboard bb,
-			SqlNode seek,
-			RelDataType targetRowType) {
-		// NOTE: Once we start accepting single-row queries as row constructors,
-		// there will be an ambiguity here for a case like X IN ((SELECT Y FROM
-		// Z)).  The SQL standard resolves the ambiguity by saying that a lone
-		// select should be interpreted as a table expression, not a row
-		// expression.  The semantic difference is that a table expression can
-		// return multiple rows.
-		if (seek instanceof SqlNodeList) {
-			return convertRowValues(
-					bb,
-					seek,
-					((SqlNodeList) seek).getList(),
-					false,
-					targetRowType);
-		} else {
-			return convertQueryRecursive(seek, false, null).project();
-		}
-	}
-
-	private RelNode convertRowValues(
-			Blackboard bb,
-			SqlNode rowList,
-			Collection<SqlNode> rows,
-			boolean allowLiteralsOnly,
-			RelDataType targetRowType) {
-		// NOTE jvs 30-Apr-2006: We combine all rows consisting entirely of
-		// literals into a single LogicalValues; this gives the optimizer a smaller
-		// input tree.  For everything else (computed expressions, row
-		// sub-queries), we union each row in as a projection on top of a
-		// LogicalOneRow.
-
-		final ImmutableList.Builder<ImmutableList<RexLiteral>> tupleList =
-				ImmutableList.builder();
-		final RelDataType rowType;
-		if (targetRowType != null) {
-			rowType = targetRowType;
-		} else {
-			rowType =
-					SqlTypeUtil.promoteToRowType(
-							typeFactory,
-							validator.getValidatedNodeType(rowList),
-							null);
-		}
-
-		final List<RelNode> unionInputs = new ArrayList<>();
-		for (SqlNode node : rows) {
-			SqlBasicCall call;
-			if (isRowConstructor(node)) {
-				call = (SqlBasicCall) node;
-				ImmutableList.Builder<RexLiteral> tuple = ImmutableList.builder();
-				for (Ord<SqlNode> operand : Ord.zip(call.operands)) {
-					RexLiteral rexLiteral =
-							convertLiteralInValuesList(
-									operand.e,
-									bb,
-									rowType,
-									operand.i);
-					if ((rexLiteral == null) && allowLiteralsOnly) {
-						return null;
-					}
-					if ((rexLiteral == null) || !config.isCreateValuesRel()) {
-						// fallback to convertRowConstructor
-						tuple = null;
-						break;
-					}
-					tuple.add(rexLiteral);
-				}
-				if (tuple != null) {
-					tupleList.add(tuple.build());
-					continue;
-				}
-			} else {
-				RexLiteral rexLiteral =
-						convertLiteralInValuesList(
-								node,
-								bb,
-								rowType,
-								0);
-				if ((rexLiteral != null) && config.isCreateValuesRel()) {
-					tupleList.add(ImmutableList.of(rexLiteral));
-					continue;
-				} else {
-					if ((rexLiteral == null) && allowLiteralsOnly) {
-						return null;
-					}
-				}
-
-				// convert "1" to "row(1)"
-				call =
-						(SqlBasicCall) SqlStdOperatorTable.ROW.createCall(
-								SqlParserPos.ZERO,
-								node);
-			}
-			unionInputs.add(convertRowConstructor(bb, call));
-		}
-		LogicalValues values =
-				LogicalValues.create(cluster, rowType, tupleList.build());
-		RelNode resultRel;
-		if (unionInputs.isEmpty()) {
-			resultRel = values;
-		} else {
-			if (!values.getTuples().isEmpty()) {
-				unionInputs.add(values);
-			}
-			resultRel = LogicalUnion.create(unionInputs, true);
-		}
-		leaves.add(resultRel);
-		return resultRel;
-	}
-
-	private RexLiteral convertLiteralInValuesList(
-			SqlNode sqlNode,
-			Blackboard bb,
-			RelDataType rowType,
-			int iField) {
-		if (!(sqlNode instanceof SqlLiteral)) {
-			return null;
-		}
-		RelDataTypeField field = rowType.getFieldList().get(iField);
-		RelDataType type = field.getType();
-		if (type.isStruct()) {
-			// null literals for weird stuff like UDT's need
-			// special handling during type flattening, so
-			// don't use LogicalValues for those
-			return null;
-		}
-
-		RexNode literalExpr =
-				exprConverter.convertLiteral(
-						bb,
-						(SqlLiteral) sqlNode);
-
-		if (!(literalExpr instanceof RexLiteral)) {
-			assert literalExpr.isA(SqlKind.CAST);
-			RexNode child = ((RexCall) literalExpr).getOperands().get(0);
-			assert RexLiteral.isNullLiteral(child);
-
-			// NOTE jvs 22-Nov-2006:  we preserve type info
-			// in LogicalValues digest, so it's OK to lose it here
-			return (RexLiteral) child;
-		}
-
-		RexLiteral literal = (RexLiteral) literalExpr;
-
-		Comparable value = literal.getValue();
-
-		if (SqlTypeUtil.isExactNumeric(type) && SqlTypeUtil.hasScale(type)) {
-			BigDecimal roundedValue =
-					NumberUtil.rescaleBigDecimal(
-							(BigDecimal) value,
-							type.getScale());
-			return rexBuilder.makeExactLiteral(
-					roundedValue,
-					type);
-		}
-
-		if ((value instanceof NlsString)
-				&& (type.getSqlTypeName() == SqlTypeName.CHAR)) {
-			// pad fixed character type
-			NlsString unpadded = (NlsString) value;
-			return rexBuilder.makeCharLiteral(
-					new NlsString(
-							Spaces.padRight(unpadded.getValue(), type.getPrecision()),
-							unpadded.getCharsetName(),
-							unpadded.getCollation()));
-		}
-		return literal;
-	}
-
-	private boolean isRowConstructor(SqlNode node) {
-		if (!(node.getKind() == SqlKind.ROW)) {
-			return false;
-		}
-		SqlCall call = (SqlCall) node;
-		return call.getOperator().getName().equalsIgnoreCase("row");
-	}
-
-	/**
-	 * Builds a list of all <code>IN</code> or <code>EXISTS</code> operators
-	 * inside SQL parse tree. Does not traverse inside queries.
-	 *
-	 * @param bb                           blackboard
-	 * @param node                         the SQL parse tree
-	 * @param logic Whether the answer needs to be in full 3-valued logic (TRUE,
-	 *              FALSE, UNKNOWN) will be required, or whether we can accept
-	 *              an approximation (say representing UNKNOWN as FALSE)
-	 * @param registerOnlyScalarSubQueries if set to true and the parse tree
-	 *                                     corresponds to a variation of a select
-	 *                                     node, only register it if it's a scalar
-	 *                                     sub-query
-	 */
-	private void findSubQueries(
-			Blackboard bb,
-			SqlNode node,
-			RelOptUtil.Logic logic,
-			boolean registerOnlyScalarSubQueries) {
-		final SqlKind kind = node.getKind();
-		switch (kind) {
-			case EXISTS:
-			case SELECT:
-			case MULTISET_QUERY_CONSTRUCTOR:
-			case MULTISET_VALUE_CONSTRUCTOR:
-			case ARRAY_QUERY_CONSTRUCTOR:
-			case CURSOR:
-			case SCALAR_QUERY:
-				if (!registerOnlyScalarSubQueries
-						|| (kind == SqlKind.SCALAR_QUERY)) {
-					bb.registerSubQuery(node, RelOptUtil.Logic.TRUE_FALSE);
-				}
-				return;
-			case IN:
-				break;
-			case NOT_IN:
-			case NOT:
-				logic = logic.negate();
-				break;
-		}
-		if (node instanceof SqlCall) {
-			switch (kind) {
-				// Do no change logic for AND, IN and NOT IN expressions;
-				// but do change logic for OR, NOT and others;
-				// EXISTS was handled already.
-				case AND:
-				case IN:
-				case NOT_IN:
-					break;
-				default:
-					logic = RelOptUtil.Logic.TRUE_FALSE_UNKNOWN;
-					break;
-			}
-			for (SqlNode operand : ((SqlCall) node).getOperandList()) {
-				if (operand != null) {
-					// In the case of an IN expression, locate scalar
-					// sub-queries so we can convert them to constants
-					findSubQueries(bb, operand, logic,
-							kind == SqlKind.IN || kind == SqlKind.NOT_IN
-									|| kind == SqlKind.SOME || kind == SqlKind.ALL
-									|| registerOnlyScalarSubQueries);
-				}
-			}
-		} else if (node instanceof SqlNodeList) {
-			for (SqlNode child : (SqlNodeList) node) {
-				findSubQueries(bb, child, logic,
-						kind == SqlKind.IN || kind == SqlKind.NOT_IN
-								|| kind == SqlKind.SOME || kind == SqlKind.ALL
-								|| registerOnlyScalarSubQueries);
-			}
-		}
-
-		// Now that we've located any scalar sub-queries inside the IN
-		// expression, register the IN expression itself.  We need to
-		// register the scalar sub-queries first so they can be converted
-		// before the IN expression is converted.
-		switch (kind) {
-			case IN:
-			case NOT_IN:
-			case SOME:
-			case ALL:
-				switch (logic) {
-					case TRUE_FALSE_UNKNOWN:
-						if (validator.getValidatedNodeType(node).isNullable()) {
-							break;
-						} else if (true) {
-							break;
-						}
-						// fall through
-					case UNKNOWN_AS_FALSE:
-						logic = RelOptUtil.Logic.TRUE;
-				}
-				bb.registerSubQuery(node, logic);
-				break;
-		}
-	}
-
-	/**
-	 * Converts an expression from {@link SqlNode} to {@link RexNode} format.
-	 *
-	 * @param node Expression to translate
-	 * @return Converted expression
-	 */
-	public RexNode convertExpression(
-			SqlNode node) {
-		Map<String, RelDataType> nameToTypeMap = Collections.emptyMap();
-		final ParameterScope scope =
-				new ParameterScope((SqlValidatorImpl) validator, nameToTypeMap);
-		final Blackboard bb = createBlackboard(scope, null, false);
-		return bb.convertExpression(node);
-	}
-
-	/**
-	 * Converts an expression from {@link SqlNode} to {@link RexNode} format,
-	 * mapping identifier references to predefined expressions.
-	 *
-	 * @param node          Expression to translate
-	 * @param nameToNodeMap map from String to {@link RexNode}; when an
-	 *                      {@link SqlIdentifier} is encountered, it is used as a
-	 *                      key and translated to the corresponding value from
-	 *                      this map
-	 * @return Converted expression
-	 */
-	public RexNode convertExpression(
-			SqlNode node,
-			Map<String, RexNode> nameToNodeMap) {
-		final Map<String, RelDataType> nameToTypeMap = new HashMap<>();
-		for (Map.Entry<String, RexNode> entry : nameToNodeMap.entrySet()) {
-			nameToTypeMap.put(entry.getKey(), entry.getValue().getType());
-		}
-		final ParameterScope scope =
-				new ParameterScope((SqlValidatorImpl) validator, nameToTypeMap);
-		final Blackboard bb = createBlackboard(scope, nameToNodeMap, false);
-		return bb.convertExpression(node);
-	}
-
-	/**
-	 * Converts a non-standard expression.
-	 *
-	 * <p>This method is an extension-point that derived classes can override. If
-	 * this method returns a null result, the normal expression translation
-	 * process will proceed. The default implementation always returns null.
-	 *
-	 * @param node Expression
-	 * @param bb   Blackboard
-	 * @return null to proceed with the usual expression translation process
-	 */
-	protected RexNode convertExtendedExpression(
-			SqlNode node,
-			Blackboard bb) {
-		return null;
-	}
-
-	private RexNode convertOver(Blackboard bb, SqlNode node) {
-		SqlCall call = (SqlCall) node;
-		SqlCall aggCall = call.operand(0);
-		SqlNode windowOrRef = call.operand(1);
-		final SqlWindow window =
-				validator.resolveWindow(windowOrRef, bb.scope, true);
-
-		// ROW_NUMBER() expects specific kind of framing.
-		if (aggCall.getKind() == SqlKind.ROW_NUMBER) {
-			window.setLowerBound(SqlWindow.createUnboundedPreceding(SqlParserPos.ZERO));
-			window.setUpperBound(SqlWindow.createCurrentRow(SqlParserPos.ZERO));
-			window.setRows(SqlLiteral.createBoolean(true, SqlParserPos.ZERO));
-		}
-		final SqlNodeList partitionList = window.getPartitionList();
-		final ImmutableList.Builder<RexNode> partitionKeys =
-				ImmutableList.builder();
-		for (SqlNode partition : partitionList) {
-			partitionKeys.add(bb.convertExpression(partition));
-		}
-		RexNode lowerBound = bb.convertExpression(window.getLowerBound());
-		RexNode upperBound = bb.convertExpression(window.getUpperBound());
-		SqlNodeList orderList = window.getOrderList();
-		if ((orderList.size() == 0) && !window.isRows()) {
-			// A logical range requires an ORDER BY clause. Use the implicit
-			// ordering of this relation. There must be one, otherwise it would
-			// have failed validation.
-			orderList = bb.scope.getOrderList();
-			if (orderList == null) {
-				throw new AssertionError(
-						"Relation should have sort key for implicit ORDER BY");
-			}
-		}
-
-		final ImmutableList.Builder<RexFieldCollation> orderKeys =
-				ImmutableList.builder();
-		for (SqlNode order : orderList) {
-			orderKeys.add(
-					bb.convertSortExpression(order,
-							RelFieldCollation.Direction.ASCENDING,
-							RelFieldCollation.NullDirection.UNSPECIFIED));
-		}
-
-		try {
-			Preconditions.checkArgument(bb.window == null,
-					"already in window agg mode");
-			bb.window = window;
-			RexNode rexAgg = exprConverter.convertCall(bb, aggCall);
-			rexAgg =
-					rexBuilder.ensureType(
-							validator.getValidatedNodeType(call), rexAgg, false);
-
-			// Walk over the tree and apply 'over' to all agg functions. This is
-			// necessary because the returned expression is not necessarily a call
-			// to an agg function. For example, AVG(x) becomes SUM(x) / COUNT(x).
-
-			final SqlLiteral q = aggCall.getFunctionQuantifier();
-			final boolean isDistinct = q != null
-					&& q.getValue() == SqlSelectKeyword.DISTINCT;
-
-			final RexShuttle visitor =
-					new HistogramShuttle(
-							partitionKeys.build(), orderKeys.build(),
-							RexWindowBound.create(window.getLowerBound(), lowerBound),
-							RexWindowBound.create(window.getUpperBound(), upperBound),
-							window,
-							isDistinct);
-			RexNode overNode = rexAgg.accept(visitor);
-
-			return overNode;
-		} finally {
-			bb.window = null;
-		}
-	}
-
-	/**
-	 * Converts a FROM clause into a relational expression.
-	 *
-	 * @param bb   Scope within which to resolve identifiers
-	 * @param from FROM clause of a query. Examples include:
-	 *
-	 *             <ul>
-	 *             <li>a single table ("SALES.EMP"),
-	 *             <li>an aliased table ("EMP AS E"),
-	 *             <li>a list of tables ("EMP, DEPT"),
-	 *             <li>an ANSI Join expression ("EMP JOIN DEPT ON EMP.DEPTNO =
-	 *             DEPT.DEPTNO"),
-	 *             <li>a VALUES clause ("VALUES ('Fred', 20)"),
-	 *             <li>a query ("(SELECT * FROM EMP WHERE GENDER = 'F')"),
-	 *             <li>or any combination of the above.
-	 *             </ul>
-	 */
-	protected void convertFrom(
-			Blackboard bb,
-			SqlNode from) {
-		if (from == null) {
-			bb.setRoot(LogicalValues.createOneRow(cluster), false);
-			return;
-		}
-
-		final SqlCall call;
-		final SqlNode[] operands;
-		switch (from.getKind()) {
-			case MATCH_RECOGNIZE:
-				convertMatchRecognize(bb, (SqlCall) from);
-				return;
-
-			case AS:
-				call = (SqlCall) from;
-				convertFrom(bb, call.operand(0));
-				if (call.operandCount() > 2
-						&& bb.root instanceof Values) {
-					final List<String> fieldNames = new ArrayList<>();
-					for (SqlNode node : Util.skip(call.getOperandList(), 2)) {
-						fieldNames.add(((SqlIdentifier) node).getSimple());
-					}
-					bb.setRoot(relBuilder.push(bb.root).rename(fieldNames).build(), true);
-				}
-				return;
-
-			case WITH_ITEM:
-				convertFrom(bb, ((SqlWithItem) from).query);
-				return;
-
-			case WITH:
-				convertFrom(bb, ((SqlWith) from).body);
-				return;
-
-			case TABLESAMPLE:
-				operands = ((SqlBasicCall) from).getOperands();
-				SqlSampleSpec sampleSpec = SqlLiteral.sampleValue(operands[1]);
-				if (sampleSpec instanceof SqlSampleSpec.SqlSubstitutionSampleSpec) {
-					String sampleName =
-							((SqlSampleSpec.SqlSubstitutionSampleSpec) sampleSpec)
-									.getName();
-					datasetStack.push(sampleName);
-					convertFrom(bb, operands[0]);
-					datasetStack.pop();
-				} else if (sampleSpec instanceof SqlSampleSpec.SqlTableSampleSpec) {
-					SqlSampleSpec.SqlTableSampleSpec tableSampleSpec =
-							(SqlSampleSpec.SqlTableSampleSpec) sampleSpec;
-					convertFrom(bb, operands[0]);
-					RelOptSamplingParameters params =
-							new RelOptSamplingParameters(
-									tableSampleSpec.isBernoulli(),
-									tableSampleSpec.getSamplePercentage(),
-									tableSampleSpec.isRepeatable(),
-									tableSampleSpec.getRepeatableSeed());
-					bb.setRoot(new Sample(cluster, bb.root, params), false);
-				} else {
-					throw new AssertionError("unknown TABLESAMPLE type: " + sampleSpec);
-				}
-				return;
-
-			case IDENTIFIER:
-				convertIdentifier(bb, (SqlIdentifier) from, null);
-				return;
-
-			case EXTEND:
-				call = (SqlCall) from;
-				SqlIdentifier id = (SqlIdentifier) call.getOperandList().get(0);
-				SqlNodeList extendedColumns = (SqlNodeList) call.getOperandList().get(1);
-				convertIdentifier(bb, id, extendedColumns);
-				return;
-
-			case JOIN:
-				final SqlJoin join = (SqlJoin) from;
-				final SqlValidatorScope scope = validator.getJoinScope(from);
-				final Blackboard fromBlackboard = createBlackboard(scope, null, false);
-				SqlNode left = join.getLeft();
-				SqlNode right = join.getRight();
-				final boolean isNatural = join.isNatural();
-				final JoinType joinType = join.getJoinType();
-				final SqlValidatorScope leftScope =
-						Util.first(validator.getJoinScope(left),
-								((DelegatingScope) bb.scope).getParent());
-				final Blackboard leftBlackboard =
-						createBlackboard(leftScope, null, false);
-				final SqlValidatorScope rightScope =
-						Util.first(validator.getJoinScope(right),
-								((DelegatingScope) bb.scope).getParent());
-				final Blackboard rightBlackboard =
-						createBlackboard(rightScope, null, false);
-				convertFrom(leftBlackboard, left);
-				RelNode leftRel = leftBlackboard.root;
-				convertFrom(rightBlackboard, right);
-				RelNode rightRel = rightBlackboard.root;
-				JoinRelType convertedJoinType = convertJoinType(joinType);
-				RexNode conditionExp;
-				final SqlValidatorNamespace leftNamespace = validator.getNamespace(left);
-				final SqlValidatorNamespace rightNamespace = validator.getNamespace(right);
-				if (isNatural) {
-					final RelDataType leftRowType = leftNamespace.getRowType();
-					final RelDataType rightRowType = rightNamespace.getRowType();
-					final List<String> columnList =
-							SqlValidatorUtil.deriveNaturalJoinColumnList(
-									catalogReader.nameMatcher(), leftRowType, rightRowType);
-					conditionExp = convertUsing(leftNamespace, rightNamespace, columnList);
-				} else {
-					conditionExp =
-							convertJoinCondition(
-									fromBlackboard,
-									leftNamespace,
-									rightNamespace,
-									join.getCondition(),
-									join.getConditionType(),
-									leftRel,
-									rightRel);
-				}
-
-				final RelNode joinRel =
-						createJoin(
-								fromBlackboard,
-								leftRel,
-								rightRel,
-								conditionExp,
-								convertedJoinType);
-				bb.setRoot(joinRel, false);
-				return;
-
-			case SELECT:
-			case INTERSECT:
-			case EXCEPT:
-			case UNION:
-				final RelNode rel = convertQueryRecursive(from, false, null).project();
-				bb.setRoot(rel, true);
-				return;
-
-			case VALUES:
-				convertValuesImpl(bb, (SqlCall) from, null);
-				return;
-
-			case UNNEST:
-				call = (SqlCall) from;
-				final List<SqlNode> nodes = call.getOperandList();
-				final SqlUnnestOperator operator = (SqlUnnestOperator) call.getOperator();
-				for (SqlNode node : nodes) {
-					replaceSubQueries(bb, node, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-				}
-				final List<RexNode> exprs = new ArrayList<>();
-				final List<String> fieldNames = new ArrayList<>();
-				for (Ord<SqlNode> node : Ord.zip(nodes)) {
-					exprs.add(bb.convertExpression(node.e));
-					fieldNames.add(validator.deriveAlias(node.e, node.i));
-				}
-				RelNode child =
-						(null != bb.root) ? bb.root : LogicalValues.createOneRow(cluster);
-				relBuilder.push(child).projectNamed(exprs, fieldNames, false);
-
-				Uncollect uncollect =
-						new Uncollect(cluster, cluster.traitSetOf(Convention.NONE),
-								relBuilder.build(), operator.withOrdinality);
-				bb.setRoot(uncollect, true);
-				return;
-
-			case COLLECTION_TABLE:
-				call = (SqlCall) from;
-
-				// Dig out real call; TABLE() wrapper is just syntactic.
-				assert call.getOperandList().size() == 1;
-				final SqlCall call2 = call.operand(0);
-				convertCollectionTable(bb, call2);
-				return;
-
-			default:
-				throw new AssertionError("not a join operator " + from);
-		}
-	}
-
-	protected void convertMatchRecognize(Blackboard bb, SqlCall call) {
-		final SqlMatchRecognize matchRecognize = (SqlMatchRecognize) call;
-		final SqlValidatorNamespace ns = validator.getNamespace(matchRecognize);
-		final SqlValidatorScope scope = validator.getMatchRecognizeScope(matchRecognize);
-
-		final Blackboard matchBb = createBlackboard(scope, null, false);
-		final RelDataType rowType = ns.getRowType();
-		// convert inner query, could be a table name or a derived table
-		SqlNode expr = matchRecognize.getTableRef();
-		convertFrom(matchBb, expr);
-		final RelNode input = matchBb.root;
-
-		// PARTITION BY
-		final SqlNodeList partitionList = matchRecognize.getPartitionList();
-		final List<RexNode> partitionKeys = new ArrayList<>();
-		for (SqlNode partition : partitionList) {
-			RexNode e = matchBb.convertExpression(partition);
-			partitionKeys.add(e);
-		}
-
-		// ORDER BY
-		final SqlNodeList orderList = matchRecognize.getOrderList();
-		final List<RelFieldCollation> orderKeys = new ArrayList<>();
-		for (SqlNode order : orderList) {
-			final RelFieldCollation.Direction direction;
-			switch (order.getKind()) {
-				case DESCENDING:
-					direction = RelFieldCollation.Direction.DESCENDING;
-					order = ((SqlCall) order).operand(0);
-					break;
-				case NULLS_FIRST:
-				case NULLS_LAST:
-					throw new AssertionError();
-				default:
-					direction = RelFieldCollation.Direction.ASCENDING;
-					break;
-			}
-			final RelFieldCollation.NullDirection nullDirection =
-					validator.getDefaultNullCollation().last(desc(direction))
-							? RelFieldCollation.NullDirection.LAST
-							: RelFieldCollation.NullDirection.FIRST;
-			RexNode e = matchBb.convertExpression(order);
-			orderKeys.add(
-					new RelFieldCollation(((RexInputRef) e).getIndex(), direction,
-							nullDirection));
-		}
-		final RelCollation orders = cluster.traitSet().canonize(RelCollations.of(orderKeys));
-
-		// convert pattern
-		final Set<String> patternVarsSet = new HashSet<>();
-		SqlNode pattern = matchRecognize.getPattern();
-		final SqlBasicVisitor<RexNode> patternVarVisitor =
-				new SqlBasicVisitor<RexNode>() {
-					@Override public RexNode visit(SqlCall call) {
-						List<SqlNode> operands = call.getOperandList();
-						List<RexNode> newOperands = new ArrayList<>();
-						for (SqlNode node : operands) {
-							newOperands.add(node.accept(this));
-						}
-						return rexBuilder.makeCall(
-								validator.getUnknownType(), call.getOperator(), newOperands);
-					}
-
-					@Override public RexNode visit(SqlIdentifier id) {
-						assert id.isSimple();
-						patternVarsSet.add(id.getSimple());
-						return rexBuilder.makeLiteral(id.getSimple());
-					}
-
-					@Override public RexNode visit(SqlLiteral literal) {
-						if (literal instanceof SqlNumericLiteral) {
-							return rexBuilder.makeExactLiteral(BigDecimal.valueOf(literal.intValue(true)));
-						} else {
-							return rexBuilder.makeLiteral(literal.booleanValue());
-						}
-					}
-				};
-		final RexNode patternNode = pattern.accept(patternVarVisitor);
-
-		SqlLiteral interval = matchRecognize.getInterval();
-		RexNode intervalNode = null;
-		if (interval != null) {
-			intervalNode = matchBb.convertLiteral(interval);
-		}
-
-		// convert subset
-		final SqlNodeList subsets = matchRecognize.getSubsetList();
-		final Map<String, TreeSet<String>> subsetMap = new HashMap<>();
-		for (SqlNode node : subsets) {
-			List<SqlNode> operands = ((SqlCall) node).getOperandList();
-			SqlIdentifier left = (SqlIdentifier) operands.get(0);
-			patternVarsSet.add(left.getSimple());
-			SqlNodeList rights = (SqlNodeList) operands.get(1);
-			final TreeSet<String> list = new TreeSet<String>();
-			for (SqlNode right : rights) {
-				assert right instanceof SqlIdentifier;
-				list.add(((SqlIdentifier) right).getSimple());
-			}
-			subsetMap.put(left.getSimple(), list);
-		}
-
-		SqlNode afterMatch = matchRecognize.getAfter();
-		if (afterMatch == null) {
-			afterMatch =
-					SqlMatchRecognize.AfterOption.SKIP_TO_NEXT_ROW.symbol(SqlParserPos.ZERO);
-		}
-
-		final RexNode after;
-		if (afterMatch instanceof SqlCall) {
-			List<SqlNode> operands = ((SqlCall) afterMatch).getOperandList();
-			SqlOperator operator = ((SqlCall) afterMatch).getOperator();
-			assert operands.size() == 1;
-			SqlIdentifier id = (SqlIdentifier) operands.get(0);
-			assert patternVarsSet.contains(id.getSimple())
-					: id.getSimple() + " not defined in pattern";
-			RexNode rex = rexBuilder.makeLiteral(id.getSimple());
-			after =
-					rexBuilder.makeCall(validator.getUnknownType(), operator,
-							ImmutableList.of(rex));
-		} else {
-			after = matchBb.convertExpression(afterMatch);
-		}
-
-		matchBb.setPatternVarRef(true);
-
-		// convert measures
-		final ImmutableMap.Builder<String, RexNode> measureNodes =
-				ImmutableMap.builder();
-		for (SqlNode measure : matchRecognize.getMeasureList()) {
-			List<SqlNode> operands = ((SqlCall) measure).getOperandList();
-			String alias = ((SqlIdentifier) operands.get(1)).getSimple();
-			RexNode rex = matchBb.convertExpression(operands.get(0));
-			measureNodes.put(alias, rex);
-		}
-
-		// convert definitions
-		final ImmutableMap.Builder<String, RexNode> definitionNodes =
-				ImmutableMap.builder();
-		for (SqlNode def : matchRecognize.getPatternDefList()) {
-			List<SqlNode> operands = ((SqlCall) def).getOperandList();
-			String alias = ((SqlIdentifier) operands.get(1)).getSimple();
-			RexNode rex = matchBb.convertExpression(operands.get(0));
-			definitionNodes.put(alias, rex);
-		}
-
-		final SqlLiteral rowsPerMatch = matchRecognize.getRowsPerMatch();
-		final boolean allRows = rowsPerMatch != null
-				&& rowsPerMatch.getValue() == SqlMatchRecognize.RowsPerMatchOption.ALL_ROWS;
-
-		matchBb.setPatternVarRef(false);
-
-		final RelFactories.MatchFactory factory =
-				RelFactories.DEFAULT_MATCH_FACTORY;
-		final RelNode rel =
-				factory.createMatch(input, patternNode,
-						rowType, matchRecognize.getStrictStart().booleanValue(),
-						matchRecognize.getStrictEnd().booleanValue(),
-						definitionNodes.build(), measureNodes.build(), after,
-						subsetMap, allRows, partitionKeys, orders, intervalNode);
-		bb.setRoot(rel, false);
-	}
-
-	private void convertIdentifier(Blackboard bb, SqlIdentifier id,
-	                               SqlNodeList extendedColumns) {
-		final SqlValidatorNamespace fromNamespace =
-				validator.getNamespace(id).resolve();
-		if (fromNamespace.getNode() != null) {
-			convertFrom(bb, fromNamespace.getNode());
-			return;
-		}
-		final String datasetName =
-				datasetStack.isEmpty() ? null : datasetStack.peek();
-		final boolean[] usedDataset = {false};
-		RelOptTable table =
-				SqlValidatorUtil.getRelOptTable(fromNamespace, catalogReader,
-						datasetName, usedDataset);
-		if (extendedColumns != null && extendedColumns.size() > 0) {
-			assert table != null;
-			final SqlValidatorTable validatorTable =
-					table.unwrap(SqlValidatorTable.class);
-			final List<RelDataTypeField> extendedFields =
-					SqlValidatorUtil.getExtendedColumns(validator.getTypeFactory(), validatorTable,
-							extendedColumns);
-			table = table.extend(extendedFields);
-		}
-		final RelNode tableRel;
-		if (config.isConvertTableAccess()) {
-			tableRel = toRel(table);
-		} else {
-			tableRel = LogicalTableScan.create(cluster, table);
-		}
-		bb.setRoot(tableRel, true);
-		if (usedDataset[0]) {
-			bb.setDataset(datasetName);
-		}
-	}
-
-	protected void convertCollectionTable(
-			Blackboard bb,
-			SqlCall call) {
-		final SqlOperator operator = call.getOperator();
-		if (operator == SqlStdOperatorTable.TABLESAMPLE) {
-			final String sampleName =
-					SqlLiteral.unchain(call.operand(0)).getValueAs(String.class);
-			datasetStack.push(sampleName);
-			SqlCall cursorCall = call.operand(1);
-			SqlNode query = cursorCall.operand(0);
-			RelNode converted = convertQuery(query, false, false).rel;
-			bb.setRoot(converted, false);
-			datasetStack.pop();
-			return;
-		}
-		replaceSubQueries(bb, call, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-		// Expand table macro if possible. It's more efficient than
-		// LogicalTableFunctionScan.
-		final SqlCallBinding callBinding =
-				new SqlCallBinding(bb.scope.getValidator(), bb.scope, call);
-		if (operator instanceof SqlUserDefinedTableMacro) {
-			final SqlUserDefinedTableMacro udf =
-					(SqlUserDefinedTableMacro) operator;
-			final TranslatableTable table =
-					udf.getTable(typeFactory, callBinding.operands());
-			final RelDataType rowType = table.getRowType(typeFactory);
-			RelOptTable relOptTable = RelOptTableImpl.create(null, rowType, table,
-					udf.getNameAsId().names);
-			RelNode converted = toRel(relOptTable);
-			bb.setRoot(converted, true);
-			return;
-		}
-
-		Type elementType;
-		if (operator instanceof SqlUserDefinedTableFunction) {
-			SqlUserDefinedTableFunction udtf = (SqlUserDefinedTableFunction) operator;
-			elementType = udtf.getElementType(typeFactory, callBinding.operands());
-		} else {
-			elementType = null;
-		}
-
-		RexNode rexCall = bb.convertExpression(call);
-		final List<RelNode> inputs = bb.retrieveCursors();
-		Set<RelColumnMapping> columnMappings =
-				getColumnMappings(operator);
-		LogicalTableFunctionScan callRel =
-				LogicalTableFunctionScan.create(
-						cluster,
-						inputs,
-						rexCall,
-						elementType,
-						validator.getValidatedNodeType(call),
-						columnMappings);
-		bb.setRoot(callRel, true);
-		afterTableFunction(bb, call, callRel);
-	}
-
-	protected void afterTableFunction(
-			SqlToRelConverter.Blackboard bb,
-			SqlCall call,
-			LogicalTableFunctionScan callRel) {
-	}
-
-	private Set<RelColumnMapping> getColumnMappings(SqlOperator op) {
-		SqlReturnTypeInference rti = op.getReturnTypeInference();
-		if (rti == null) {
-			return null;
-		}
-		if (rti instanceof TableFunctionReturnTypeInference) {
-			TableFunctionReturnTypeInference tfrti =
-					(TableFunctionReturnTypeInference) rti;
-			return tfrti.getColumnMappings();
-		} else {
-			return null;
-		}
-	}
-
-	protected RelNode createJoin(
-			Blackboard bb,
-			RelNode leftRel,
-			RelNode rightRel,
-			RexNode joinCond,
-			JoinRelType joinType) {
-		assert joinCond != null;
-
-		final CorrelationUse p = getCorrelationUse(bb, rightRel);
-		if (p != null) {
-			LogicalCorrelate corr = LogicalCorrelate.create(leftRel, p.r,
-					p.id, p.requiredColumns, SemiJoinType.of(joinType));
-			if (!joinCond.isAlwaysTrue()) {
-				final RelFactories.FilterFactory factory =
-						RelFactories.DEFAULT_FILTER_FACTORY;
-				return factory.createFilter(corr, joinCond);
-			}
-			return corr;
-		}
-
-		final Join originalJoin =
-				(Join) RelFactories.DEFAULT_JOIN_FACTORY.createJoin(leftRel, rightRel,
-						joinCond, ImmutableSet.of(), joinType, false);
-
-		return RelOptUtil.pushDownJoinConditions(originalJoin, relBuilder);
-	}
-
-	private CorrelationUse getCorrelationUse(Blackboard bb, final RelNode r0) {
-		final Set<CorrelationId> correlatedVariables =
-				RelOptUtil.getVariablesUsed(r0);
-		if (correlatedVariables.isEmpty()) {
-			return null;
-		}
-		final ImmutableBitSet.Builder requiredColumns = ImmutableBitSet.builder();
-		final List<CorrelationId> correlNames = new ArrayList<>();
-
-		// All correlations must refer the same namespace since correlation
-		// produces exactly one correlation source.
-		// The same source might be referenced by different variables since
-		// DeferredLookups are not de-duplicated at create time.
-		SqlValidatorNamespace prevNs = null;
-
-		for (CorrelationId correlName : correlatedVariables) {
-			DeferredLookup lookup =
-					mapCorrelToDeferred.get(correlName);
-			RexFieldAccess fieldAccess = lookup.getFieldAccess(correlName);
-			String originalRelName = lookup.getOriginalRelName();
-			String originalFieldName = fieldAccess.getField().getName();
-
-			final SqlNameMatcher nameMatcher =
-					bb.getValidator().getCatalogReader().nameMatcher();
-			final SqlValidatorScope.ResolvedImpl resolved =
-					new SqlValidatorScope.ResolvedImpl();
-			lookup.bb.scope.resolve(ImmutableList.of(originalRelName),
-					nameMatcher, false, resolved);
-			assert resolved.count() == 1;
-			final SqlValidatorScope.Resolve resolve = resolved.only();
-			final SqlValidatorNamespace foundNs = resolve.namespace;
-			final RelDataType rowType = resolve.rowType();
-			final int childNamespaceIndex = resolve.path.steps().get(0).i;
-			final SqlValidatorScope ancestorScope = resolve.scope;
-			boolean correlInCurrentScope = bb.scope.isWithin(ancestorScope);
-
-			if (!correlInCurrentScope) {
-				continue;
-			}
-
-			if (prevNs == null) {
-				prevNs = foundNs;
-			} else {
-				assert prevNs == foundNs : "All correlation variables should resolve"
-						+ " to the same namespace."
-						+ " Prev ns=" + prevNs
-						+ ", new ns=" + foundNs;
-			}
-
-			int namespaceOffset = 0;
-			if (childNamespaceIndex > 0) {
-				// If not the first child, need to figure out the width
-				// of output types from all the preceding namespaces
-				assert ancestorScope instanceof ListScope;
-				List<SqlValidatorNamespace> children =
-						((ListScope) ancestorScope).getChildren();
-
-				for (int i = 0; i < childNamespaceIndex; i++) {
-					SqlValidatorNamespace child = children.get(i);
-					namespaceOffset +=
-							child.getRowType().getFieldCount();
-				}
-			}
-
-			RexFieldAccess topLevelFieldAccess = fieldAccess;
-			while (topLevelFieldAccess.getReferenceExpr() instanceof RexFieldAccess) {
-				topLevelFieldAccess = (RexFieldAccess) topLevelFieldAccess.getReferenceExpr();
-			}
-			final RelDataTypeField field = rowType.getFieldList()
-					.get(topLevelFieldAccess.getField().getIndex() - namespaceOffset);
-			int pos = namespaceOffset + field.getIndex();
-
-			assert field.getType()
-					== topLevelFieldAccess.getField().getType();
-
-			assert pos != -1;
-
-			if (bb.mapRootRelToFieldProjection.containsKey(bb.root)) {
-				// bb.root is an aggregate and only projects group by
-				// keys.
-				Map<Integer, Integer> exprProjection =
-						bb.mapRootRelToFieldProjection.get(bb.root);
-
-				// sub-query can reference group by keys projected from
-				// the root of the outer relation.
-				if (exprProjection.containsKey(pos)) {
-					pos = exprProjection.get(pos);
-				} else {
-					// correl not grouped
-					throw new AssertionError("Identifier '" + originalRelName + "."
-							+ originalFieldName + "' is not a group expr");
-				}
-			}
-
-			requiredColumns.set(pos);
-			correlNames.add(correlName);
-		}
-
-		if (correlNames.isEmpty()) {
-			// None of the correlating variables originated in this scope.
-			return null;
-		}
-
-		RelNode r = r0;
-		if (correlNames.size() > 1) {
-			// The same table was referenced more than once.
-			// So we deduplicate.
-			r = DeduplicateCorrelateVariables.go(rexBuilder, correlNames.get(0),
-					Util.skip(correlNames), r0);
-			// Add new node to leaves.
-			leaves.add(r);
-		}
-		return new CorrelationUse(correlNames.get(0), requiredColumns.build(), r);
-	}
-
-	/**
-	 * Determines whether a sub-query is non-correlated. Note that a
-	 * non-correlated sub-query can contain correlated references, provided those
-	 * references do not reference select statements that are parents of the
-	 * sub-query.
-	 *
-	 * @param subq the sub-query
-	 * @param bb   blackboard used while converting the sub-query, i.e., the
-	 *             blackboard of the parent query of this sub-query
-	 * @return true if the sub-query is non-correlated
-	 */
-	private boolean isSubQueryNonCorrelated(RelNode subq, Blackboard bb) {
-		Set<CorrelationId> correlatedVariables = RelOptUtil.getVariablesUsed(subq);
-		for (CorrelationId correlName : correlatedVariables) {
-			DeferredLookup lookup = mapCorrelToDeferred.get(correlName);
-			String originalRelName = lookup.getOriginalRelName();
-
-			final SqlNameMatcher nameMatcher =
-					lookup.bb.scope.getValidator().getCatalogReader().nameMatcher();
-			final SqlValidatorScope.ResolvedImpl resolved =
-					new SqlValidatorScope.ResolvedImpl();
-			lookup.bb.scope.resolve(ImmutableList.of(originalRelName), nameMatcher,
-					false, resolved);
-
-			SqlValidatorScope ancestorScope = resolved.only().scope;
-
-			// If the correlated reference is in a scope that's "above" the
-			// sub-query, then this is a correlated sub-query.
-			SqlValidatorScope parentScope = bb.scope;
-			do {
-				if (ancestorScope == parentScope) {
-					return false;
-				}
-				if (parentScope instanceof DelegatingScope) {
-					parentScope = ((DelegatingScope) parentScope).getParent();
-				} else {
-					break;
-				}
-			} while (parentScope != null);
-		}
-		return true;
-	}
-
-	/**
-	 * Returns a list of fields to be prefixed to each relational expression.
-	 *
-	 * @return List of system fields
-	 */
-	protected List<RelDataTypeField> getSystemFields() {
-		return Collections.emptyList();
-	}
-
-	private RexNode convertJoinCondition(Blackboard bb,
-	                                     SqlValidatorNamespace leftNamespace,
-	                                     SqlValidatorNamespace rightNamespace,
-	                                     SqlNode condition,
-	                                     JoinConditionType conditionType,
-	                                     RelNode leftRel,
-	                                     RelNode rightRel) {
-		if (condition == null) {
-			return rexBuilder.makeLiteral(true);
-		}
-		bb.setRoot(ImmutableList.of(leftRel, rightRel));
-		replaceSubQueries(bb, condition, RelOptUtil.Logic.UNKNOWN_AS_FALSE);
-		switch (conditionType) {
-			case ON:
-				bb.setRoot(ImmutableList.of(leftRel, rightRel));
-				return bb.convertExpression(condition);
-			case USING:
-				final SqlNodeList list = (SqlNodeList) condition;
-				final List<String> nameList = new ArrayList<>();
-				for (SqlNode columnName : list) {
-					final SqlIdentifier id = (SqlIdentifier) columnName;
-					String name = id.getSimple();
-					nameList.add(name);
-				}
-				return convertUsing(leftNamespace, rightNamespace, nameList);
-			default:
-				throw Util.unexpected(conditionType);
-		}
-	}
-
-	/**
-	 * Returns an expression for matching columns of a USING clause or inferred
-	 * from NATURAL JOIN. "a JOIN b USING (x, y)" becomes "a.x = b.x AND a.y =
-	 * b.y". Returns null if the column list is empty.
-	 *
-	 * @param leftNamespace Namespace of left input to join
-	 * @param rightNamespace Namespace of right input to join
-	 * @param nameList List of column names to join on
-	 * @return Expression to match columns from name list, or true if name list
-	 * is empty
-	 */
-	private RexNode convertUsing(SqlValidatorNamespace leftNamespace,
-	                             SqlValidatorNamespace rightNamespace,
-	                             List<String> nameList) {
-		final SqlNameMatcher nameMatcher = catalogReader.nameMatcher();
-		final List<RexNode> list = new ArrayList<>();
-		for (String name : nameList) {
-			List<RexNode> operands = new ArrayList<>();
-			int offset = 0;
-			for (SqlValidatorNamespace n : ImmutableList.of(leftNamespace,
-					rightNamespace)) {
-				final RelDataType rowType = n.getRowType();
-				final RelDataTypeField field = nameMatcher.field(rowType, name);
-				operands.add(
-						rexBuilder.makeInputRef(field.getType(),
-								offset + field.getIndex()));
-				offset += rowType.getFieldList().size();
-			}
-			list.add(rexBuilder.makeCall(SqlStdOperatorTable.EQUALS, operands));
-		}
-		return RexUtil.composeConjunction(rexBuilder, list, false);
-	}
-
-	private static JoinRelType convertJoinType(JoinType joinType) {
-		switch (joinType) {
-			case COMMA:
-			case INNER:
-			case CROSS:
-				return JoinRelType.INNER;
-			case FULL:
-				return JoinRelType.FULL;
-			case LEFT:
-				return JoinRelType.LEFT;
-			case RIGHT:
-				return JoinRelType.RIGHT;
-			default:
-				throw Util.unexpected(joinType);
-		}
-	}
-
-	/**
-	 * Converts the SELECT, GROUP BY and HAVING clauses of an aggregate query.
-	 *
-	 * <p>This method extracts SELECT, GROUP BY and HAVING clauses, and creates
-	 * an {@link AggConverter}, then delegates to {@link #createAggImpl}.
-	 * Derived class may override this method to change any of those clauses or
-	 * specify a different {@link AggConverter}.
-	 *
-	 * @param bb            Scope within which to resolve identifiers
-	 * @param select        Query
-	 * @param orderExprList Additional expressions needed to implement ORDER BY
-	 */
-	protected void convertAgg(
-			Blackboard bb,
-			SqlSelect select,
-			List<SqlNode> orderExprList) {
-		assert bb.root != null : "precondition: child != null";
-		SqlNodeList groupList = select.getGroup();
-		SqlNodeList selectList = select.getSelectList();
-		SqlNode having = select.getHaving();
-
-		final AggConverter aggConverter = new AggConverter(bb, select);
-		createAggImpl(
-				bb,
-				aggConverter,
-				selectList,
-				groupList,
-				having,
-				orderExprList);
-	}
-
-	protected final void createAggImpl(
-			Blackboard bb,
-			final AggConverter aggConverter,
-			SqlNodeList selectList,
-			SqlNodeList groupList,
-			SqlNode having,
-			List<SqlNode> orderExprList) {
-		// Find aggregate functions in SELECT and HAVING clause
-		final AggregateFinder aggregateFinder = new AggregateFinder();
-		selectList.accept(aggregateFinder);
-		if (having != null) {
-			having.accept(aggregateFinder);
-		}
-
-		// first replace the sub-queries inside the aggregates
-		// because they will provide input rows to the aggregates.
-		replaceSubQueries(bb, aggregateFinder.list,
-				RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-		// also replace sub-queries inside filters in the aggregates
-		replaceSubQueries(bb, aggregateFinder.filterList,
-				RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-		// If group-by clause is missing, pretend that it has zero elements.
-		if (groupList == null) {
-			groupList = SqlNodeList.EMPTY;
-		}
-
-		replaceSubQueries(bb, groupList, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-		// register the group exprs
-
-		// build a map to remember the projections from the top scope to the
-		// output of the current root.
-		//
-		// Calcite allows expressions, not just column references in
-		// group by list. This is not SQL 2003 compliant, but hey.
-
-		final AggregatingSelectScope scope = aggConverter.aggregatingSelectScope;
-		final AggregatingSelectScope.Resolved r = scope.resolved.get();
-		for (SqlNode groupExpr : r.groupExprList) {
-			aggConverter.addGroupExpr(groupExpr);
-		}
-
-		final RexNode havingExpr;
-		final List<Pair<RexNode, String>> projects = new ArrayList<>();
-
-		try {
-			Preconditions.checkArgument(bb.agg == null, "already in agg mode");
-			bb.agg = aggConverter;
-
-			// convert the select and having expressions, so that the
-			// agg converter knows which aggregations are required
-
-			selectList.accept(aggConverter);
-			// Assert we don't have dangling items left in the stack
-			assert !aggConverter.inOver;
-			for (SqlNode expr : orderExprList) {
-				expr.accept(aggConverter);
-				assert !aggConverter.inOver;
-			}
-			if (having != null) {
-				having.accept(aggConverter);
-				assert !aggConverter.inOver;
-			}
-
-			// compute inputs to the aggregator
-			List<Pair<RexNode, String>> preExprs = aggConverter.getPreExprs();
-
-			if (preExprs.size() == 0) {
-				// Special case for COUNT(*), where we can end up with no inputs
-				// at all.  The rest of the system doesn't like 0-tuples, so we
-				// select a dummy constant here.
-				final RexNode zero = rexBuilder.makeExactLiteral(BigDecimal.ZERO);
-				preExprs = ImmutableList.of(Pair.of(zero, (String) null));
-			}
-
-			final RelNode inputRel = bb.root;
-
-			// Project the expressions required by agg and having.
-			bb.setRoot(
-					relBuilder.push(inputRel)
-							.projectNamed(Pair.left(preExprs), Pair.right(preExprs), false)
-							.build(),
-					false);
-			bb.mapRootRelToFieldProjection.put(bb.root, r.groupExprProjection);
-
-			// REVIEW jvs 31-Oct-2007:  doesn't the declaration of
-			// monotonicity here assume sort-based aggregation at
-			// the physical level?
-
-			// Tell bb which of group columns are sorted.
-			bb.columnMonotonicities.clear();
-			for (SqlNode groupItem : groupList) {
-				bb.columnMonotonicities.add(
-						bb.scope.getMonotonicity(groupItem));
-			}
-
-			// Add the aggregator
-			bb.setRoot(
-					createAggregate(bb, r.groupSet, r.groupSets,
-							aggConverter.getAggCalls()),
-					false);
-
-			bb.mapRootRelToFieldProjection.put(bb.root, r.groupExprProjection);
-
-			// Replace sub-queries in having here and modify having to use
-			// the replaced expressions
-			if (having != null) {
-				SqlNode newHaving = pushDownNotForIn(bb.scope, having);
-				replaceSubQueries(bb, newHaving, RelOptUtil.Logic.UNKNOWN_AS_FALSE);
-				havingExpr = bb.convertExpression(newHaving);
-			} else {
-				havingExpr = relBuilder.literal(true);
-			}
-
-			// Now convert the other sub-queries in the select list.
-			// This needs to be done separately from the sub-query inside
-			// any aggregate in the select list, and after the aggregate rel
-			// is allocated.
-			replaceSubQueries(bb, selectList, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-			// Now sub-queries in the entire select list have been converted.
-			// Convert the select expressions to get the final list to be
-			// projected.
-			int k = 0;
-
-			// For select expressions, use the field names previously assigned
-			// by the validator. If we derive afresh, we might generate names
-			// like "EXPR$2" that don't match the names generated by the
-			// validator. This is especially the case when there are system
-			// fields; system fields appear in the relnode's rowtype but do not
-			// (yet) appear in the validator type.
-			final SelectScope selectScope =
-					SqlValidatorUtil.getEnclosingSelectScope(bb.scope);
-			assert selectScope != null;
-			final SqlValidatorNamespace selectNamespace =
-					validator.getNamespace(selectScope.getNode());
-			final List<String> names =
-					selectNamespace.getRowType().getFieldNames();
-			int sysFieldCount = selectList.size() - names.size();
-			for (SqlNode expr : selectList) {
-				projects.add(
-						Pair.of(bb.convertExpression(expr),
-								k < sysFieldCount
-										? validator.deriveAlias(expr, k++)
-										: names.get(k++ - sysFieldCount)));
-			}
-
-			for (SqlNode expr : orderExprList) {
-				projects.add(
-						Pair.of(bb.convertExpression(expr),
-								validator.deriveAlias(expr, k++)));
-			}
-		} finally {
-			bb.agg = null;
-		}
-
-		// implement HAVING (we have already checked that it is non-trivial)
-		relBuilder.push(bb.root);
-		if (havingExpr != null) {
-			relBuilder.filter(havingExpr);
-		}
-
-		// implement the SELECT list
-		relBuilder.project(Pair.left(projects), Pair.right(projects))
-				.rename(Pair.right(projects));
-		bb.setRoot(relBuilder.build(), false);
-
-		// Tell bb which of group columns are sorted.
-		bb.columnMonotonicities.clear();
-		for (SqlNode selectItem : selectList) {
-			bb.columnMonotonicities.add(
-					bb.scope.getMonotonicity(selectItem));
-		}
-	}
-
-	/**
-	 * Creates an Aggregate.
-	 *
-	 * <p>In case the aggregate rel changes the order in which it projects
-	 * fields, the <code>groupExprProjection</code> parameter is provided, and
-	 * the implementation of this method may modify it.
-	 *
-	 * <p>The <code>sortedCount</code> parameter is the number of expressions
-	 * known to be monotonic. These expressions must be on the leading edge of
-	 * the grouping keys. The default implementation of this method ignores this
-	 * parameter.
-	 *
-	 * @param bb       Blackboard
-	 * @param groupSet Bit set of ordinals of grouping columns
-	 * @param groupSets Grouping sets
-	 * @param aggCalls Array of calls to aggregate functions
-	 * @return LogicalAggregate
-	 */
-	protected RelNode createAggregate(Blackboard bb, ImmutableBitSet groupSet,
-	                                  ImmutableList<ImmutableBitSet> groupSets, List<AggregateCall> aggCalls) {
-		return LogicalAggregate.create(bb.root, groupSet, groupSets, aggCalls);
-	}
-
-	public RexDynamicParam convertDynamicParam(
-			final SqlDynamicParam dynamicParam) {
-		// REVIEW jvs 8-Jan-2005:  dynamic params may be encountered out of
-		// order.  Should probably cross-check with the count from the parser
-		// at the end and make sure they all got filled in.  Why doesn't List
-		// have a resize() method?!?  Make this a utility.
-		while (dynamicParam.getIndex() >= dynamicParamSqlNodes.size()) {
-			dynamicParamSqlNodes.add(null);
-		}
-
-		dynamicParamSqlNodes.set(
-				dynamicParam.getIndex(),
-				dynamicParam);
-		return rexBuilder.makeDynamicParam(
-				getDynamicParamType(dynamicParam.getIndex()),
-				dynamicParam.getIndex());
-	}
-
-	/**
-	 * Creates a list of collations required to implement the ORDER BY clause,
-	 * if there is one. Populates <code>extraOrderExprs</code> with any sort
-	 * expressions which are not in the select clause.
-	 *
-	 * @param bb              Scope within which to resolve identifiers
-	 * @param select          Select clause. Never null, because we invent a
-	 *                        dummy SELECT if ORDER BY is applied to a set
-	 *                        operation (UNION etc.)
-	 * @param orderList       Order by clause, may be null
-	 * @param extraOrderExprs Sort expressions which are not in the select
-	 *                        clause (output)
-	 * @param collationList   List of collations (output)
-	 */
-	protected void gatherOrderExprs(
-			Blackboard bb,
-			SqlSelect select,
-			SqlNodeList orderList,
-			List<SqlNode> extraOrderExprs,
-			List<RelFieldCollation> collationList) {
-		// TODO:  add validation rules to SqlValidator also
-		assert bb.root != null : "precondition: child != null";
-		assert select != null;
-		if (orderList == null) {
-			return;
-		}
-		for (SqlNode orderItem : orderList) {
-			collationList.add(
-					convertOrderItem(select, orderItem, extraOrderExprs,
-							RelFieldCollation.Direction.ASCENDING,
-							RelFieldCollation.NullDirection.UNSPECIFIED));
-		}
-	}
-
-	protected RelFieldCollation convertOrderItem(
-			SqlSelect select,
-			SqlNode orderItem, List<SqlNode> extraExprs,
-			RelFieldCollation.Direction direction,
-			RelFieldCollation.NullDirection nullDirection) {
-		assert select != null;
-		// Handle DESC keyword, e.g. 'select a, b from t order by a desc'.
-		switch (orderItem.getKind()) {
-			case DESCENDING:
-				return convertOrderItem(
-						select,
-						((SqlCall) orderItem).operand(0),
-						extraExprs,
-						RelFieldCollation.Direction.DESCENDING,
-						nullDirection);
-			case NULLS_FIRST:
-				return convertOrderItem(
-						select,
-						((SqlCall) orderItem).operand(0),
-						extraExprs,
-						direction,
-						RelFieldCollation.NullDirection.FIRST);
-			case NULLS_LAST:
-				return convertOrderItem(
-						select,
-						((SqlCall) orderItem).operand(0),
-						extraExprs,
-						direction,
-						RelFieldCollation.NullDirection.LAST);
-		}
-
-		SqlNode converted = validator.expandOrderExpr(select, orderItem);
-
-		switch (nullDirection) {
-			case UNSPECIFIED:
-				nullDirection = validator.getDefaultNullCollation().last(desc(direction))
-						? RelFieldCollation.NullDirection.LAST
-						: RelFieldCollation.NullDirection.FIRST;
-		}
-
-		// Scan the select list and order exprs for an identical expression.
-		final SelectScope selectScope = validator.getRawSelectScope(select);
-		int ordinal = -1;
-		for (SqlNode selectItem : selectScope.getExpandedSelectList()) {
-			++ordinal;
-			if (converted.equalsDeep(stripAs(selectItem), Litmus.IGNORE)) {
-				return new RelFieldCollation(ordinal, direction, nullDirection);
-			}
-		}
-
-		for (SqlNode extraExpr : extraExprs) {
-			++ordinal;
-			if (converted.equalsDeep(extraExpr, Litmus.IGNORE)) {
-				return new RelFieldCollation(ordinal, direction, nullDirection);
-			}
-		}
-
-		// TODO:  handle collation sequence
-		// TODO: flag expressions as non-standard
-
-		extraExprs.add(converted);
-		return new RelFieldCollation(ordinal + 1, direction, nullDirection);
-	}
-
-	private static boolean desc(RelFieldCollation.Direction direction) {
-		switch (direction) {
-			case DESCENDING:
-			case STRICTLY_DESCENDING:
-				return true;
-			default:
-				return false;
-		}
-	}
-
-	@Deprecated // to be removed before 2.0
-	protected boolean enableDecorrelation() {
-		// disable sub-query decorrelation when needed.
-		// e.g. if outer joins are not supported.
-		return config.isDecorrelationEnabled();
-	}
-
-	protected RelNode decorrelateQuery(RelNode rootRel) {
-		return RelDecorrelator.decorrelateQuery(rootRel, relBuilder);
-	}
-
-	/**
-	 * Returns whether to trim unused fields as part of the conversion process.
-	 *
-	 * @return Whether to trim unused fields
-	 */
-	@Deprecated // to be removed before 2.0
-	public boolean isTrimUnusedFields() {
-		return config.isTrimUnusedFields();
-	}
-
-	/**
-	 * Recursively converts a query to a relational expression.
-	 *
-	 * @param query         Query
-	 * @param top           Whether this query is the top-level query of the
-	 *                      statement
-	 * @param targetRowType Target row type, or null
-	 * @return Relational expression
-	 */
-	protected RelRoot convertQueryRecursive(SqlNode query, boolean top,
-	                                        RelDataType targetRowType) {
-		final SqlKind kind = query.getKind();
-		switch (kind) {
-			case SELECT:
-				return RelRoot.of(convertSelect((SqlSelect) query, top), kind);
-			case INSERT:
-				return RelRoot.of(convertInsert((SqlInsert) query), kind);
-			case DELETE:
-				return RelRoot.of(convertDelete((SqlDelete) query), kind);
-			case UPDATE:
-				return RelRoot.of(convertUpdate((SqlUpdate) query), kind);
-			case MERGE:
-				return RelRoot.of(convertMerge((SqlMerge) query), kind);
-			case UNION:
-			case INTERSECT:
-			case EXCEPT:
-				return RelRoot.of(convertSetOp((SqlCall) query), kind);
-			case WITH:
-				return convertWith((SqlWith) query, top);
-			case VALUES:
-				return RelRoot.of(convertValues((SqlCall) query, targetRowType), kind);
-			default:
-				throw new AssertionError("not a query: " + query);
-		}
-	}
-
-	/**
-	 * Converts a set operation (UNION, INTERSECT, MINUS) into relational
-	 * expressions.
-	 *
-	 * @param call Call to set operator
-	 * @return Relational expression
-	 */
-	protected RelNode convertSetOp(SqlCall call) {
-		final RelNode left =
-				convertQueryRecursive(call.operand(0), false, null).project();
-		final RelNode right =
-				convertQueryRecursive(call.operand(1), false, null).project();
-		switch (call.getKind()) {
-			case UNION:
-				return LogicalUnion.create(ImmutableList.of(left, right), all(call));
-
-			case INTERSECT:
-				return LogicalIntersect.create(ImmutableList.of(left, right), all(call));
-
-			case EXCEPT:
-				return LogicalMinus.create(ImmutableList.of(left, right), all(call));
-
-			default:
-				throw Util.unexpected(call.getKind());
-		}
-	}
-
-	private boolean all(SqlCall call) {
-		return ((SqlSetOperator) call.getOperator()).isAll();
-	}
-
-	protected RelNode convertInsert(SqlInsert call) {
-		RelOptTable targetTable = getTargetTable(call);
-
-		final RelDataType targetRowType =
-				validator.getValidatedNodeType(call);
-		assert targetRowType != null;
-		RelNode sourceRel =
-				convertQueryRecursive(call.getSource(), false, targetRowType).project();
-		RelNode massagedRel = convertColumnList(call, sourceRel);
-
-		return createModify(targetTable, massagedRel);
-	}
-
-	/** Creates a relational expression to modify a table or modifiable view. */
-	private RelNode createModify(RelOptTable targetTable, RelNode source) {
-		final ModifiableTable modifiableTable =
-				targetTable.unwrap(ModifiableTable.class);
-		if (modifiableTable != null
-				&& modifiableTable == targetTable.unwrap(Table.class)) {
-			return modifiableTable.toModificationRel(cluster, targetTable,
-					catalogReader, source, LogicalTableModify.Operation.INSERT, null,
-					null, false);
-		}
-		final ModifiableView modifiableView =
-				targetTable.unwrap(ModifiableView.class);
-		if (modifiableView != null) {
-			final Table delegateTable = modifiableView.getTable();
-			final RelDataType delegateRowType = delegateTable.getRowType(typeFactory);
-			final RelOptTable delegateRelOptTable =
-					RelOptTableImpl.create(null, delegateRowType, delegateTable,
-							modifiableView.getTablePath());
-			final RelNode newSource =
-					createSource(targetTable, source, modifiableView, delegateRowType);
-			return createModify(delegateRelOptTable, newSource);
-		}
-		return LogicalTableModify.create(targetTable, catalogReader, source,
-				LogicalTableModify.Operation.INSERT, null, null, false);
-	}
-
-	/** Wraps a relational expression in the projects and filters implied by
-	 * a {@link ModifiableView}.
-	 *
-	 * <p>The input relational expression is suitable for inserting into the view,
-	 * and the returned relational expression is suitable for inserting into its
-	 * delegate table.
-	 *
-	 * <p>In principle, the delegate table of a view might be another modifiable
-	 * view, and if so, the process can be repeated. */
-	private RelNode createSource(RelOptTable targetTable, RelNode source,
-	                             ModifiableView modifiableView, RelDataType delegateRowType) {
-		final ImmutableIntList mapping = modifiableView.getColumnMapping();
-		assert mapping.size() == targetTable.getRowType().getFieldCount();
-
-		// For columns represented in the mapping, the expression is just a field
-		// reference.
-		final Map<Integer, RexNode> projectMap = new HashMap<>();
-		final List<RexNode> filters = new ArrayList<>();
-		for (int i = 0; i < mapping.size(); i++) {
-			int target = mapping.get(i);
-			if (target >= 0) {
-				projectMap.put(target, RexInputRef.of(i, source.getRowType()));
-			}
-		}
-
-		// For columns that are not in the mapping, and have a constraint of the
-		// form "column = value", the expression is the literal "value".
-		//
-		// If a column has multiple constraints, the extra ones will become a
-		// filter.
-		final RexNode constraint =
-				modifiableView.getConstraint(rexBuilder, delegateRowType);
-		RelOptUtil.inferViewPredicates(projectMap, filters, constraint);
-		final List<Pair<RexNode, String>> projects = new ArrayList<>();
-		for (RelDataTypeField field : delegateRowType.getFieldList()) {
-			RexNode node = projectMap.get(field.getIndex());
-			if (node == null) {
-				node = rexBuilder.makeNullLiteral(field.getType());
-			}
-			projects.add(
-					Pair.of(rexBuilder.ensureType(field.getType(), node, false),
-							field.getName()));
-		}
-
-		return relBuilder.push(source)
-				.projectNamed(Pair.left(projects), Pair.right(projects), false)
-				.filter(filters)
-				.build();
-	}
-
-	private RelOptTable.ToRelContext createToRelContext() {
-		return new RelOptTable.ToRelContext() {
-			public RelOptCluster getCluster() {
-				return cluster;
-			}
-
-			@Override public RelRoot expandView(
-					RelDataType rowType,
-					String queryString,
-					List<String> schemaPath,
-					List<String> viewPath) {
-				return viewExpander.expandView(rowType, queryString, schemaPath, viewPath);
-			}
-
-		};
-	}
-
-	public RelNode toRel(final RelOptTable table) {
-		final RelNode scan = table.toRel(createToRelContext());
-
-		final InitializerExpressionFactory ief =
-				Util.first(table.unwrap(InitializerExpressionFactory.class),
-						NullInitializerExpressionFactory.INSTANCE);
-
-		// Lazily create a blackboard that contains all non-generated columns.
-		final Supplier<Blackboard> bb = () -> {
-			RexNode sourceRef = rexBuilder.makeRangeReference(scan);
-			return createInsertBlackboard(table, sourceRef,
-					table.getRowType().getFieldNames());
-		};
-
-		int virtualCount = 0;
-		final List<RexNode> list = new ArrayList<>();
-		for (RelDataTypeField f : table.getRowType().getFieldList()) {
-			final ColumnStrategy strategy =
-					ief.generationStrategy(table, f.getIndex());
-			switch (strategy) {
-				case VIRTUAL:
-					list.add(ief.newColumnDefaultValue(table, f.getIndex(), bb.get()));
-					++virtualCount;
-					break;
-				default:
-					list.add(
-							rexBuilder.makeInputRef(scan,
-									RelOptTableImpl.realOrdinal(table, f.getIndex())));
-			}
-		}
-		if (virtualCount > 0) {
-			relBuilder.push(scan);
-			relBuilder.project(list);
-			return relBuilder.build();
-		}
-		return scan;
-	}
-
-	protected RelOptTable getTargetTable(SqlNode call) {
-		final SqlValidatorNamespace targetNs = validator.getNamespace(call);
-		if (targetNs.isWrapperFor(SqlValidatorImpl.DmlNamespace.class)) {
-			final SqlValidatorImpl.DmlNamespace dmlNamespace =
-					targetNs.unwrap(SqlValidatorImpl.DmlNamespace.class);
-			return SqlValidatorUtil.getRelOptTable(dmlNamespace, catalogReader, null, null);
-		}
-		final SqlValidatorNamespace resolvedNamespace = targetNs.resolve();
-		return SqlValidatorUtil.getRelOptTable(resolvedNamespace, catalogReader, null, null);
-	}
-
-	/**
-	 * Creates a source for an INSERT statement.
-	 *
-	 * <p>If the column list is not specified, source expressions match target
-	 * columns in order.
-	 *
-	 * <p>If the column list is specified, Source expressions are mapped to
-	 * target columns by name via targetColumnList, and may not cover the entire
-	 * target table. So, we'll make up a full row, using a combination of
-	 * default values and the source expressions provided.
-	 *
-	 * @param call      Insert expression
-	 * @param source Source relational expression
-	 * @return Converted INSERT statement
-	 */
-	protected RelNode convertColumnList(final SqlInsert call, RelNode source) {
-		RelDataType sourceRowType = source.getRowType();
-		final RexNode sourceRef =
-				rexBuilder.makeRangeReference(sourceRowType, 0, false);
-		final List<String> targetColumnNames = new ArrayList<>();
-		final List<RexNode> columnExprs = new ArrayList<>();
-		collectInsertTargets(call, sourceRef, targetColumnNames, columnExprs);
-
-		final RelOptTable targetTable = getTargetTable(call);
-		final RelDataType targetRowType = RelOptTableImpl.realRowType(targetTable);
-		final List<RelDataTypeField> targetFields = targetRowType.getFieldList();
-		final List<RexNode> sourceExps =
-				new ArrayList<>(
-						Collections.nCopies(targetFields.size(), null));
-		final List<String> fieldNames =
-				new ArrayList<>(
-						Collections.nCopies(targetFields.size(), null));
-
-		final InitializerExpressionFactory initializerFactory =
-				getInitializerFactory(validator.getNamespace(call).getTable());
-
-		// Walk the name list and place the associated value in the
-		// expression list according to the ordinal value returned from
-		// the table construct, leaving nulls in the list for columns
-		// that are not referenced.
-		final SqlNameMatcher nameMatcher = catalogReader.nameMatcher();
-		for (Pair<String, RexNode> p : Pair.zip(targetColumnNames, columnExprs)) {
-			RelDataTypeField field = nameMatcher.field(targetRowType, p.left);
-			assert field != null : "column " + p.left + " not found";
-			sourceExps.set(field.getIndex(), p.right);
-		}
-
-		// Lazily create a blackboard that contains all non-generated columns.
-		final Supplier<Blackboard> bb = () ->
-				createInsertBlackboard(targetTable, sourceRef, targetColumnNames);
-
-		// Walk the expression list and get default values for any columns
-		// that were not supplied in the statement. Get field names too.
-		for (int i = 0; i < targetFields.size(); ++i) {
-			final RelDataTypeField field = targetFields.get(i);
-			final String fieldName = field.getName();
-			fieldNames.set(i, fieldName);
-			if (sourceExps.get(i) == null
-					|| sourceExps.get(i).getKind() == SqlKind.DEFAULT) {
-				sourceExps.set(i,
-						initializerFactory.newColumnDefaultValue(targetTable, i, bb.get()));
-
-				// bare nulls are dangerous in the wrong hands
-				sourceExps.set(i,
-						castNullLiteralIfNeeded(sourceExps.get(i), field.getType()));
-			}
-		}
-
-		return relBuilder.push(source)
-				.projectNamed(sourceExps, fieldNames, false)
-				.build();
-	}
-
-	/** Creates a blackboard for translating the expressions of generated columns
-	 * in an INSERT statement. */
-	private Blackboard createInsertBlackboard(RelOptTable targetTable,
-	                                          RexNode sourceRef, List<String> targetColumnNames) {
-		final Map<String, RexNode> nameToNodeMap = new HashMap<>();
-		int j = 0;
-
-		// Assign expressions for non-generated columns.
-		final List<ColumnStrategy> strategies = targetTable.getColumnStrategies();
-		final List<String> targetFields = targetTable.getRowType().getFieldNames();
-		for (String targetColumnName : targetColumnNames) {
-			final int i = targetFields.indexOf(targetColumnName);
-			switch (strategies.get(i)) {
-				case STORED:
-				case VIRTUAL:
-					break;
-				default:
-					nameToNodeMap.put(targetColumnName,
-							rexBuilder.makeFieldAccess(sourceRef, j++));
-			}
-		}
-		return createBlackboard(null, nameToNodeMap, false);
-	}
-
-	private InitializerExpressionFactory getInitializerFactory(
-			SqlValidatorTable validatorTable) {
-		// We might unwrap a null instead of a InitializerExpressionFactory.
-		final Table table = unwrap(validatorTable, Table.class);
-		if (table != null) {
-			InitializerExpressionFactory f =
-					unwrap(table, InitializerExpressionFactory.class);
-			if (f != null) {
-				return f;
-			}
-		}
-		return NullInitializerExpressionFactory.INSTANCE;
-	}
-
-	private static <T> T unwrap(Object o, Class<T> clazz) {
-		if (o instanceof Wrapper) {
-			return ((Wrapper) o).unwrap(clazz);
-		}
-		return null;
-	}
-
-	private RexNode castNullLiteralIfNeeded(RexNode node, RelDataType type) {
-		if (!RexLiteral.isNullLiteral(node)) {
-			return node;
-		}
-		return rexBuilder.makeCast(type, node);
-	}
-
-	/**
-	 * Given an INSERT statement, collects the list of names to be populated and
-	 * the expressions to put in them.
-	 *
-	 * @param call              Insert statement
-	 * @param sourceRef         Expression representing a row from the source
-	 *                          relational expression
-	 * @param targetColumnNames List of target column names, to be populated
-	 * @param columnExprs       List of expressions, to be populated
-	 */
-	protected void collectInsertTargets(
-			SqlInsert call,
-			final RexNode sourceRef,
-			final List<String> targetColumnNames,
-			List<RexNode> columnExprs) {
-		final RelOptTable targetTable = getTargetTable(call);
-		final RelDataType tableRowType = targetTable.getRowType();
-		SqlNodeList targetColumnList = call.getTargetColumnList();
-		if (targetColumnList == null) {
-			if (validator.getConformance().isInsertSubsetColumnsAllowed()) {
-				final RelDataType targetRowType =
-						typeFactory.createStructType(
-								tableRowType.getFieldList()
-										.subList(0, sourceRef.getType().getFieldCount()));
-				targetColumnNames.addAll(targetRowType.getFieldNames());
-			} else {
-				targetColumnNames.addAll(tableRowType.getFieldNames());
-			}
-		} else {
-			for (int i = 0; i < targetColumnList.size(); i++) {
-				SqlIdentifier id = (SqlIdentifier) targetColumnList.get(i);
-				RelDataTypeField field =
-						SqlValidatorUtil.getTargetField(
-								tableRowType, typeFactory, id, catalogReader, targetTable);
-				assert field != null : "column " + id.toString() + " not found";
-				targetColumnNames.add(field.getName());
-			}
-		}
-
-		final Blackboard bb =
-				createInsertBlackboard(targetTable, sourceRef, targetColumnNames);
-
-		// Next, assign expressions for generated columns.
-		final List<ColumnStrategy> strategies = targetTable.getColumnStrategies();
-		for (String columnName : targetColumnNames) {
-			final int i = tableRowType.getFieldNames().indexOf(columnName);
-			final RexNode expr;
-			switch (strategies.get(i)) {
-				case STORED:
-					final InitializerExpressionFactory f =
-							Util.first(targetTable.unwrap(InitializerExpressionFactory.class),
-									NullInitializerExpressionFactory.INSTANCE);
-					expr = f.newColumnDefaultValue(targetTable, i, bb);
-					break;
-				case VIRTUAL:
-					expr = null;
-					break;
-				default:
-					expr = bb.nameToNodeMap.get(columnName);
-			}
-			columnExprs.add(expr);
-		}
-
-		// Remove virtual columns from the list.
-		for (int i = 0; i < targetColumnNames.size(); i++) {
-			if (columnExprs.get(i) == null) {
-				columnExprs.remove(i);
-				targetColumnNames.remove(i);
-				--i;
-			}
-		}
-	}
-
-	private RelNode convertDelete(SqlDelete call) {
-		RelOptTable targetTable = getTargetTable(call);
-		RelNode sourceRel = convertSelect(call.getSourceSelect(), false);
-		return LogicalTableModify.create(targetTable, catalogReader, sourceRel,
-				LogicalTableModify.Operation.DELETE, null, null, false);
-	}
-
-	private RelNode convertUpdate(SqlUpdate call) {
-		final SqlValidatorScope scope = validator.getWhereScope(call.getSourceSelect());
-		Blackboard bb = createBlackboard(scope, null, false);
-
-		Builder<RexNode> rexNodeSourceExpressionListBuilder = ImmutableList.builder();
-		for (SqlNode n : call.getSourceExpressionList()) {
-			RexNode rn = bb.convertExpression(n);
-			rexNodeSourceExpressionListBuilder.add(rn);
-		}
-
-		RelOptTable targetTable = getTargetTable(call);
-
-		// convert update column list from SqlIdentifier to String
-		final List<String> targetColumnNameList = new ArrayList<>();
-		final RelDataType targetRowType = targetTable.getRowType();
-		for (SqlNode node : call.getTargetColumnList()) {
-			SqlIdentifier id = (SqlIdentifier) node;
-			RelDataTypeField field =
-					SqlValidatorUtil.getTargetField(
-							targetRowType, typeFactory, id, catalogReader, targetTable);
-			assert field != null : "column " + id.toString() + " not found";
-			targetColumnNameList.add(field.getName());
-		}
-
-		RelNode sourceRel = convertSelect(call.getSourceSelect(), false);
-
-		return LogicalTableModify.create(targetTable, catalogReader, sourceRel,
-				LogicalTableModify.Operation.UPDATE, targetColumnNameList,
-				rexNodeSourceExpressionListBuilder.build(), false);
-	}
-
-	private RelNode convertMerge(SqlMerge call) {
-		RelOptTable targetTable = getTargetTable(call);
-
-		// convert update column list from SqlIdentifier to String
-		final List<String> targetColumnNameList = new ArrayList<>();
-		final RelDataType targetRowType = targetTable.getRowType();
-		SqlUpdate updateCall = call.getUpdateCall();
-		if (updateCall != null) {
-			for (SqlNode targetColumn : updateCall.getTargetColumnList()) {
-				SqlIdentifier id = (SqlIdentifier) targetColumn;
-				RelDataTypeField field =
-						SqlValidatorUtil.getTargetField(
-								targetRowType, typeFactory, id, catalogReader, targetTable);
-				assert field != null : "column " + id.toString() + " not found";
-				targetColumnNameList.add(field.getName());
-			}
-		}
-
-		// replace the projection of the source select with a
-		// projection that contains the following:
-		// 1) the expressions corresponding to the new insert row (if there is
-		//    an insert)
-		// 2) all columns from the target table (if there is an update)
-		// 3) the set expressions in the update call (if there is an update)
-
-		// first, convert the merge's source select to construct the columns
-		// from the target table and the set expressions in the update call
-		RelNode mergeSourceRel = convertSelect(call.getSourceSelect(), false);
-
-		// then, convert the insert statement so we can get the insert
-		// values expressions
-		SqlInsert insertCall = call.getInsertCall();
-		int nLevel1Exprs = 0;
-		List<RexNode> level1InsertExprs = null;
-		List<RexNode> level2InsertExprs = null;
-		if (insertCall != null) {
-			RelNode insertRel = convertInsert(insertCall);
-
-			// if there are 2 level of projections in the insert source, combine
-			// them into a single project; level1 refers to the topmost project;
-			// the level1 projection contains references to the level2
-			// expressions, except in the case where no target expression was
-			// provided, in which case, the expression is the default value for
-			// the column; or if the expressions directly map to the source
-			// table
-			level1InsertExprs =
-					((LogicalProject) insertRel.getInput(0)).getProjects();
-			if (insertRel.getInput(0).getInput(0) instanceof LogicalProject) {
-				level2InsertExprs =
-						((LogicalProject) insertRel.getInput(0).getInput(0))
-								.getProjects();
-			}
-			nLevel1Exprs = level1InsertExprs.size();
-		}
-
-		LogicalJoin join = (LogicalJoin) mergeSourceRel.getInput(0);
-		int nSourceFields = join.getLeft().getRowType().getFieldCount();
-		final List<RexNode> projects = new ArrayList<>();
-		for (int level1Idx = 0; level1Idx < nLevel1Exprs; level1Idx++) {
-			if ((level2InsertExprs != null)
-					&& (level1InsertExprs.get(level1Idx) instanceof RexInputRef)) {
-				int level2Idx =
-						((RexInputRef) level1InsertExprs.get(level1Idx)).getIndex();
-				projects.add(level2InsertExprs.get(level2Idx));
-			} else {
-				projects.add(level1InsertExprs.get(level1Idx));
-			}
-		}
-		if (updateCall != null) {
-			final LogicalProject project = (LogicalProject) mergeSourceRel;
-			projects.addAll(
-					Util.skip(project.getProjects(), nSourceFields));
-		}
-
-		relBuilder.push(join)
-				.project(projects);
-
-		return LogicalTableModify.create(targetTable, catalogReader,
-				relBuilder.build(), LogicalTableModify.Operation.MERGE,
-				targetColumnNameList, null, false);
-	}
-
-	/**
-	 * Converts an identifier into an expression in a given scope. For example,
-	 * the "empno" in "select empno from emp join dept" becomes "emp.empno".
-	 */
-	private RexNode convertIdentifier(
-			Blackboard bb,
-			SqlIdentifier identifier) {
-		// first check for reserved identifiers like CURRENT_USER
-		final SqlCall call = SqlUtil.makeCall(opTab, identifier);
-		if (call != null) {
-			return bb.convertExpression(call);
-		}
-
-		String pv = null;
-		if (bb.isPatternVarRef && identifier.names.size() > 1) {
-			pv = identifier.names.get(0);
-		}
-
-		final SqlQualified qualified;
-		if (bb.scope != null) {
-			qualified = bb.scope.fullyQualify(identifier);
-		} else {
-			qualified = SqlQualified.create(null, 1, null, identifier);
-		}
-		final Pair<RexNode, Map<String, Integer>> e0 = bb.lookupExp(qualified);
-		RexNode e = e0.left;
-		for (String name : qualified.suffix()) {
-			if (e == e0.left && e0.right != null) {
-				int i = e0.right.get(name);
-				e = rexBuilder.makeFieldAccess(e, i);
-			} else {
-				final boolean caseSensitive = true; // name already fully-qualified
-				if (identifier.isStar() && bb.scope instanceof MatchRecognizeScope) {
-					e = rexBuilder.makeFieldAccess(e, 0);
-				} else {
-					e = rexBuilder.makeFieldAccess(e, name, caseSensitive);
-				}
-			}
-		}
-		if (e instanceof RexInputRef) {
-			// adjust the type to account for nulls introduced by outer joins
-			e = adjustInputRef(bb, (RexInputRef) e);
-			if (pv != null) {
-				e = RexPatternFieldRef.of(pv, (RexInputRef) e);
-			}
-		}
-
-		if (e0.left instanceof RexCorrelVariable) {
-			assert e instanceof RexFieldAccess;
-			final RexNode prev =
-					bb.mapCorrelateToRex.put(((RexCorrelVariable) e0.left).id,
-							(RexFieldAccess) e);
-			assert prev == null;
-		}
-		return e;
-	}
-
-	/**
-	 * Adjusts the type of a reference to an input field to account for nulls
-	 * introduced by outer joins; and adjusts the offset to match the physical
-	 * implementation.
-	 *
-	 * @param bb       Blackboard
-	 * @param inputRef Input ref
-	 * @return Adjusted input ref
-	 */
-	protected RexNode adjustInputRef(
-			Blackboard bb,
-			RexInputRef inputRef) {
-		RelDataTypeField field = bb.getRootField(inputRef);
-		if (field != null) {
-			return rexBuilder.makeInputRef(
-					field.getType(),
-					inputRef.getIndex());
-		}
-		return inputRef;
-	}
-
-	/**
-	 * Converts a row constructor into a relational expression.
-	 *
-	 * @param bb             Blackboard
-	 * @param rowConstructor Row constructor expression
-	 * @return Relational expression which returns a single row.
-	 */
-	private RelNode convertRowConstructor(
-			Blackboard bb,
-			SqlCall rowConstructor) {
-		Preconditions.checkArgument(isRowConstructor(rowConstructor));
-		final List<SqlNode> operands = rowConstructor.getOperandList();
-		return convertMultisets(operands, bb);
-	}
-
-	private RelNode convertCursor(Blackboard bb, SubQuery subQuery) {
-		final SqlCall cursorCall = (SqlCall) subQuery.node;
-		assert cursorCall.operandCount() == 1;
-		SqlNode query = cursorCall.operand(0);
-		RelNode converted = convertQuery(query, false, false).rel;
-		int iCursor = bb.cursors.size();
-		bb.cursors.add(converted);
-		subQuery.expr =
-				new RexInputRef(
-						iCursor,
-						converted.getRowType());
-		return converted;
-	}
-
-	private RelNode convertMultisets(final List<SqlNode> operands,
-	                                 Blackboard bb) {
-		// NOTE: Wael 2/04/05: this implementation is not the most efficient in
-		// terms of planning since it generates XOs that can be reduced.
-		final List<Object> joinList = new ArrayList<>();
-		List<SqlNode> lastList = new ArrayList<>();
-		for (int i = 0; i < operands.size(); i++) {
-			SqlNode operand = operands.get(i);
-			if (!(operand instanceof SqlCall)) {
-				lastList.add(operand);
-				continue;
-			}
-
-			final SqlCall call = (SqlCall) operand;
-			final RelNode input;
-			switch (call.getKind()) {
-				case MULTISET_VALUE_CONSTRUCTOR:
-				case ARRAY_VALUE_CONSTRUCTOR:
-					final SqlNodeList list =
-							new SqlNodeList(call.getOperandList(), call.getParserPosition());
-					CollectNamespace nss =
-							(CollectNamespace) validator.getNamespace(call);
-					Blackboard usedBb;
-					if (null != nss) {
-						usedBb = createBlackboard(nss.getScope(), null, false);
-					} else {
-						usedBb =
-								createBlackboard(new ListScope(bb.scope) {
-									public SqlNode getNode() {
-										return call;
-									}
-								}, null, false);
-					}
-					RelDataType multisetType = validator.getValidatedNodeType(call);
-					((SqlValidatorImpl) validator).setValidatedNodeType(list,
-							multisetType.getComponentType());
-					input = convertQueryOrInList(usedBb, list, null);
-					break;
-				case MULTISET_QUERY_CONSTRUCTOR:
-				case ARRAY_QUERY_CONSTRUCTOR:
-					final RelRoot root = convertQuery(call.operand(0), false, true);
-					input = root.rel;
-					break;
-				default:
-					lastList.add(operand);
-					continue;
-			}
-
-			if (lastList.size() > 0) {
-				joinList.add(lastList);
-			}
-			lastList = new ArrayList<>();
-			Collect collect =
-					new Collect(
-							cluster,
-							cluster.traitSetOf(Convention.NONE),
-							input,
-							validator.deriveAlias(call, i));
-			joinList.add(collect);
-		}
-
-		if (joinList.size() == 0) {
-			joinList.add(lastList);
-		}
-
-		for (int i = 0; i < joinList.size(); i++) {
-			Object o = joinList.get(i);
-			if (o instanceof List) {
-				@SuppressWarnings("unchecked")
-				List<SqlNode> projectList = (List<SqlNode>) o;
-				final List<RexNode> selectList = new ArrayList<>();
-				final List<String> fieldNameList = new ArrayList<>();
-				for (int j = 0; j < projectList.size(); j++) {
-					SqlNode operand = projectList.get(j);
-					selectList.add(bb.convertExpression(operand));
-
-					// REVIEW angel 5-June-2005: Use deriveAliasFromOrdinal
-					// instead of deriveAlias to match field names from
-					// SqlRowOperator. Otherwise, get error   Type
-					// 'RecordType(INTEGER EMPNO)' has no field 'EXPR$0' when
-					// doing   select * from unnest(     select multiset[empno]
-					// from sales.emps);
-
-					fieldNameList.add(SqlUtil.deriveAliasFromOrdinal(j));
-				}
-
-				relBuilder.push(LogicalValues.createOneRow(cluster))
-						.projectNamed(selectList, fieldNameList, true);
-
-				joinList.set(i, relBuilder.build());
-			}
-		}
-
-		RelNode ret = (RelNode) joinList.get(0);
-		for (int i = 1; i < joinList.size(); i++) {
-			RelNode relNode = (RelNode) joinList.get(i);
-			ret =
-					RelFactories.DEFAULT_JOIN_FACTORY.createJoin(
-							ret,
-							relNode,
-							rexBuilder.makeLiteral(true),
-							ImmutableSet.of(),
-							JoinRelType.INNER,
-							false);
-		}
-		return ret;
-	}
-
-	private void convertSelectList(
-			Blackboard bb,
-			SqlSelect select,
-			List<SqlNode> orderList) {
-		SqlNodeList selectList = select.getSelectList();
-		selectList = validator.expandStar(selectList, select, false);
-
-		replaceSubQueries(bb, selectList, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-
-		List<String> fieldNames = new ArrayList<>();
-		final List<RexNode> exprs = new ArrayList<>();
-		final Collection<String> aliases = new TreeSet<>();
-
-		// Project any system fields. (Must be done before regular select items,
-		// because offsets may be affected.)
-		final List<SqlMonotonicity> columnMonotonicityList = new ArrayList<>();
-		extraSelectItems(
-				bb,
-				select,
-				exprs,
-				fieldNames,
-				aliases,
-				columnMonotonicityList);
-
-		// Project select clause.
-		int i = -1;
-		for (SqlNode expr : selectList) {
-			++i;
-			exprs.add(bb.convertExpression(expr));
-			fieldNames.add(deriveAlias(expr, aliases, i));
-		}
-
-		// Project extra fields for sorting.
-		for (SqlNode expr : orderList) {
-			++i;
-			SqlNode expr2 = validator.expandOrderExpr(select, expr);
-			exprs.add(bb.convertExpression(expr2));
-			fieldNames.add(deriveAlias(expr, aliases, i));
-		}
-
-		fieldNames = SqlValidatorUtil.uniquify(fieldNames,
-				catalogReader.nameMatcher().isCaseSensitive());
-
-		relBuilder.push(bb.root)
-				.projectNamed(exprs, fieldNames, true);
-		bb.setRoot(relBuilder.build(), false);
-
-		assert bb.columnMonotonicities.isEmpty();
-		bb.columnMonotonicities.addAll(columnMonotonicityList);
-		for (SqlNode selectItem : selectList) {
-			bb.columnMonotonicities.add(
-					selectItem.getMonotonicity(bb.scope));
-		}
-	}
-
-	/**
-	 * Adds extra select items. The default implementation adds nothing; derived
-	 * classes may add columns to exprList, nameList, aliasList and
-	 * columnMonotonicityList.
-	 *
-	 * @param bb                     Blackboard
-	 * @param select                 Select statement being translated
-	 * @param exprList               List of expressions in select clause
-	 * @param nameList               List of names, one per column
-	 * @param aliasList              Collection of aliases that have been used
-	 *                               already
-	 * @param columnMonotonicityList List of monotonicity, one per column
-	 */
-	protected void extraSelectItems(
-			Blackboard bb,
-			SqlSelect select,
-			List<RexNode> exprList,
-			List<String> nameList,
-			Collection<String> aliasList,
-			List<SqlMonotonicity> columnMonotonicityList) {
-	}
-
-	private String deriveAlias(
-			final SqlNode node,
-			Collection<String> aliases,
-			final int ordinal) {
-		String alias = validator.deriveAlias(node, ordinal);
-		if ((alias == null) || aliases.contains(alias)) {
-			String aliasBase = (alias == null) ? "EXPR$" : alias;
-			for (int j = 0;; j++) {
-				alias = aliasBase + j;
-				if (!aliases.contains(alias)) {
-					break;
-				}
-			}
-		}
-		aliases.add(alias);
-		return alias;
-	}
-
-	/**
-	 * Converts a WITH sub-query into a relational expression.
-	 */
-	public RelRoot convertWith(SqlWith with, boolean top) {
-		return convertQuery(with.body, false, top);
-	}
-
-	/**
-	 * Converts a SELECT statement's parse tree into a relational expression.
-	 */
-	public RelNode convertValues(
-			SqlCall values,
-			RelDataType targetRowType) {
-		final SqlValidatorScope scope = validator.getOverScope(values);
-		assert scope != null;
-		final Blackboard bb = createBlackboard(scope, null, false);
-		convertValuesImpl(bb, values, targetRowType);
-		return bb.root;
-	}
-
-	/**
-	 * Converts a values clause (as in "INSERT INTO T(x,y) VALUES (1,2)") into a
-	 * relational expression.
-	 *
-	 * @param bb            Blackboard
-	 * @param values        Call to SQL VALUES operator
-	 * @param targetRowType Target row type
-	 */
-	private void convertValuesImpl(
-			Blackboard bb,
-			SqlCall values,
-			RelDataType targetRowType) {
-		// Attempt direct conversion to LogicalValues; if that fails, deal with
-		// fancy stuff like sub-queries below.
-		RelNode valuesRel =
-				convertRowValues(
-						bb,
-						values,
-						values.getOperandList(),
-						true,
-						targetRowType);
-		if (valuesRel != null) {
-			bb.setRoot(valuesRel, true);
-			return;
-		}
-
-		final List<RelNode> unionRels = new ArrayList<>();
-		for (SqlNode rowConstructor1 : values.getOperandList()) {
-			SqlCall rowConstructor = (SqlCall) rowConstructor1;
-			Blackboard tmpBb = createBlackboard(bb.scope, null, false);
-			replaceSubQueries(tmpBb, rowConstructor,
-					RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
-			final List<Pair<RexNode, String>> exps = new ArrayList<>();
-			for (Ord<SqlNode> operand : Ord.zip(rowConstructor.getOperandList())) {
-				exps.add(
-						Pair.of(
-								tmpBb.convertExpression(operand.e),
-								validator.deriveAlias(operand.e, operand.i)));
-			}
-			RelNode in =
-					(null == tmpBb.root)
-							? LogicalValues.createOneRow(cluster)
-							: tmpBb.root;
-			unionRels.add(relBuilder.push(in)
-					.project(Pair.left(exps), Pair.right(exps))
-					.build());
-		}
-
-		if (unionRels.size() == 0) {
-			throw new AssertionError("empty values clause");
-		} else if (unionRels.size() == 1) {
-			bb.setRoot(
-					unionRels.get(0),
-					true);
-		} else {
-			bb.setRoot(
-					LogicalUnion.create(unionRels, true),
-					true);
-		}
-
-		// REVIEW jvs 22-Jan-2004:  should I add
-		// mapScopeToLux.put(validator.getScope(values),bb.root);
-		// ?
-	}
-
-	//~ Inner Classes ----------------------------------------------------------
-
-	/**
-	 * Workspace for translating an individual SELECT statement (or sub-SELECT).
-	 */
-	protected class Blackboard implements SqlRexContext, SqlVisitor<RexNode>,
-			InitializerContext {
-		/**
-		 * Collection of {@link RelNode} objects which correspond to a SELECT
-		 * statement.
-		 */
-		public final SqlValidatorScope scope;
-		private final Map<String, RexNode> nameToNodeMap;
-		public RelNode root;
-		private List<RelNode> inputs;
-		private final Map<CorrelationId, RexFieldAccess> mapCorrelateToRex =
-				new HashMap<>();
-
-		private boolean isPatternVarRef = false;
-
-		final List<RelNode> cursors = new ArrayList<>();
-
-		/**
-		 * List of <code>IN</code> and <code>EXISTS</code> nodes inside this
-		 * <code>SELECT</code> statement (but not inside sub-queries).
-		 */
-		private final Set<SubQuery> subQueryList = new LinkedHashSet<>();
-
-		/**
-		 * Workspace for building aggregates.
-		 */
-		AggConverter agg;
-
-		/**
-		 * When converting window aggregate, we need to know if the window is
-		 * guaranteed to be non-empty.
-		 */
-		SqlWindow window;
-
-		/**
-		 * Project the groupby expressions out of the root of this sub-select.
-		 * Sub-queries can reference group by expressions projected from the
-		 * "right" to the sub-query.
-		 */
-		private final Map<RelNode, Map<Integer, Integer>> mapRootRelToFieldProjection =
-				new HashMap<>();
-
-		private final List<SqlMonotonicity> columnMonotonicities =
-				new ArrayList<>();
-
-		private final List<RelDataTypeField> systemFieldList = new ArrayList<>();
-		final boolean top;
-
-		private final InitializerExpressionFactory initializerExpressionFactory =
-				new NullInitializerExpressionFactory();
-
-		/**
-		 * Creates a Blackboard.
-		 *
-		 * @param scope         Name-resolution scope for expressions validated
-		 *                      within this query. Can be null if this Blackboard is
-		 *                      for a leaf node, say
-		 * @param nameToNodeMap Map which translates the expression to map a
-		 *                      given parameter into, if translating expressions;
-		 *                      null otherwise
-		 * @param top           Whether this is the root of the query
-		 */
-		protected Blackboard(SqlValidatorScope scope,
-		                     Map<String, RexNode> nameToNodeMap, boolean top) {
-			this.scope = scope;
-			this.nameToNodeMap = nameToNodeMap;
-			this.top = top;
-		}
-
-		public void setPatternVarRef(boolean isVarRef) {
-			this.isPatternVarRef = isVarRef;
-		}
-
-		public RexNode register(
-				RelNode rel,
-				JoinRelType joinType) {
-			return register(rel, joinType, null);
-		}
-
-		/**
-		 * Registers a relational expression.
-		 *
-		 * @param rel               Relational expression
-		 * @param joinType          Join type
-		 * @param leftKeys LHS of IN clause, or null for expressions
-		 *                          other than IN
-		 * @return Expression with which to refer to the row (or partial row)
-		 * coming from this relational expression's side of the join
-		 */
-		public RexNode register(
-				RelNode rel,
-				JoinRelType joinType,
-				List<RexNode> leftKeys) {
-			assert joinType != null;
-			if (root == null) {
-				assert leftKeys == null;
-				setRoot(rel, false);
-				return rexBuilder.makeRangeReference(
-						root.getRowType(),
-						0,
-						false);
-			}
-
-			final RexNode joinCond;
-			final int origLeftInputCount = root.getRowType().getFieldCount();
-			if (leftKeys != null) {
-				List<RexNode> newLeftInputExprs = new ArrayList<>();
-				for (int i = 0; i < origLeftInputCount; i++) {
-					newLeftInputExprs.add(rexBuilder.makeInputRef(root, i));
-				}
-
-				final List<Integer> leftJoinKeys = new ArrayList<>();
-				for (RexNode leftKey : leftKeys) {
-					int index = newLeftInputExprs.indexOf(leftKey);
-					if (index < 0 || joinType == JoinRelType.LEFT) {
-						index = newLeftInputExprs.size();
-						newLeftInputExprs.add(leftKey);
-					}
-					leftJoinKeys.add(index);
-				}
-
-				RelNode newLeftInput =
-						relBuilder.push(root)
-								.project(newLeftInputExprs)
-								.build();
-
-				// maintain the group by mapping in the new LogicalProject
-				if (mapRootRelToFieldProjection.containsKey(root)) {
-					mapRootRelToFieldProjection.put(
-							newLeftInput,
-							mapRootRelToFieldProjection.get(root));
-				}
-
-				setRoot(newLeftInput, false);
-
-				// right fields appear after the LHS fields.
-				final int rightOffset = root.getRowType().getFieldCount()
-						- newLeftInput.getRowType().getFieldCount();
-				final List<Integer> rightKeys =
-						Util.range(rightOffset, rightOffset + leftKeys.size());
-
-				joinCond =
-						RelOptUtil.createEquiJoinCondition(newLeftInput, leftJoinKeys,
-								rel, rightKeys, rexBuilder);
-			} else {
-				joinCond = rexBuilder.makeLiteral(true);
-			}
-
-			int leftFieldCount = root.getRowType().getFieldCount();
-			final RelNode join =
-					createJoin(
-							this,
-							root,
-							rel,
-							joinCond,
-							joinType);
-
-			setRoot(join, false);
-
-			if (leftKeys != null
-					&& joinType == JoinRelType.LEFT) {
-				final int leftKeyCount = leftKeys.size();
-				int rightFieldLength = rel.getRowType().getFieldCount();
-				assert leftKeyCount == rightFieldLength - 1;
-
-				final int rexRangeRefLength = leftKeyCount + rightFieldLength;
-				RelDataType returnType =
-						typeFactory.createStructType(
-								new AbstractList<Map.Entry<String, RelDataType>>() {
-									public Map.Entry<String, RelDataType> get(
-											int index) {
-										return join.getRowType().getFieldList()
-												.get(origLeftInputCount + index);
-									}
-
-									public int size() {
-										return rexRangeRefLength;
-									}
-								});
-
-				return rexBuilder.makeRangeReference(
-						returnType,
-						origLeftInputCount,
-						false);
-			} else {
-				return rexBuilder.makeRangeReference(
-						rel.getRowType(),
-						leftFieldCount,
-						joinType.generatesNullsOnRight());
-			}
-		}
-
-		/**
-		 * Sets a new root relational expression, as the translation process
-		 * backs its way further up the tree.
-		 *
-		 * @param root New root relational expression
-		 * @param leaf Whether the relational expression is a leaf, that is,
-		 *             derived from an atomic relational expression such as a table
-		 *             name in the from clause, or the projection on top of a
-		 *             select-sub-query. In particular, relational expressions
-		 *             derived from JOIN operators are not leaves, but set
-		 *             expressions are.
-		 */
-		public void setRoot(RelNode root, boolean leaf) {
-			setRoot(
-					Collections.singletonList(root), root, root instanceof LogicalJoin);
-			if (leaf) {
-				leaves.add(root);
-			}
-			this.columnMonotonicities.clear();
-		}
-
-		private void setRoot(
-				List<RelNode> inputs,
-				RelNode root,
-				boolean hasSystemFields) {
-			this.inputs = inputs;
-			this.root = root;
-			this.systemFieldList.clear();
-			if (hasSystemFields) {
-				this.systemFieldList.addAll(getSystemFields());
-			}
-		}
-
-		/**
-		 * Notifies this Blackboard that the root just set using
-		 * {@link #setRoot(RelNode, boolean)} was derived using dataset
-		 * substitution.
-		 *
-		 * <p>The default implementation is not interested in such
-		 * notifications, and does nothing.
-		 *
-		 * @param datasetName Dataset name
-		 */
-		public void setDataset(String datasetName) {
-		}
-
-		void setRoot(List<RelNode> inputs) {
-			setRoot(inputs, null, false);
-		}
-
-		/**
-		 * Returns an expression with which to reference a from-list item.
-		 *
-		 * @param qualified the alias of the from item
-		 * @return a {@link RexFieldAccess} or {@link RexRangeRef}, or null if
-		 * not found
-		 */
-		Pair<RexNode, Map<String, Integer>> lookupExp(SqlQualified qualified) {
-			if (nameToNodeMap != null && qualified.prefixLength == 1) {
-				RexNode node = nameToNodeMap.get(qualified.identifier.names.get(0));
-				if (node == null) {
-					throw new AssertionError("Unknown identifier '" + qualified.identifier
-							+ "' encountered while expanding expression");
-				}
-				return Pair.of(node, null);
-			}
-			final SqlNameMatcher nameMatcher =
-					scope.getValidator().getCatalogReader().nameMatcher();
-			final SqlValidatorScope.ResolvedImpl resolved =
-					new SqlValidatorScope.ResolvedImpl();
-			scope.resolve(qualified.prefix(), nameMatcher, false, resolved);
-			if (!(resolved.count() == 1)) {
-				return null;
-			}
-			final SqlValidatorScope.Resolve resolve = resolved.only();
-			final RelDataType rowType = resolve.rowType();
-
-			// Found in current query's from list.  Find which from item.
-			// We assume that the order of the from clause items has been
-			// preserved.
-			final SqlValidatorScope ancestorScope = resolve.scope;
-			boolean isParent = ancestorScope != scope;
-			if ((inputs != null) && !isParent) {
-				final LookupContext rels =
-						new LookupContext(this, inputs, systemFieldList.size());
-				final RexNode node = lookup(resolve.path.steps().get(0).i, rels);
-				if (node == null) {
-					return null;
-				} else {
-					final Map<String, Integer> fieldOffsets = new HashMap<>();
-					for (RelDataTypeField f : resolve.rowType().getFieldList()) {
-						if (!fieldOffsets.containsKey(f.getName())) {
-							fieldOffsets.put(f.getName(), f.getIndex());
-						}
-					}
-					final Map<String, Integer> map = ImmutableMap.copyOf(fieldOffsets);
-					return Pair.of(node, map);
-				}
-			} else {
-				// We're referencing a relational expression which has not been
-				// converted yet. This occurs when from items are correlated,
-				// e.g. "select from emp as emp join emp.getDepts() as dept".
-				// Create a temporary expression.
-				DeferredLookup lookup =
-						new DeferredLookup(this, qualified.identifier.names.get(0));
-				final CorrelationId correlId = cluster.createCorrel();
-				mapCorrelToDeferred.put(correlId, lookup);
-				if (resolve.path.steps().get(0).i < 0) {
-					return Pair.of(rexBuilder.makeCorrel(rowType, correlId), null);
-				} else {
-					final RelDataTypeFactory.Builder builder = typeFactory.builder();
-					final ListScope ancestorScope1 = (ListScope) resolve.scope;
-					final ImmutableMap.Builder<String, Integer> fields =
-							ImmutableMap.builder();
-					int i = 0;
-					int offset = 0;
-					for (SqlValidatorNamespace c : ancestorScope1.getChildren()) {
-						builder.addAll(c.getRowType().getFieldList());
-						if (i == resolve.path.steps().get(0).i) {
-							for (RelDataTypeField field : c.getRowType().getFieldList()) {
-								fields.put(field.getName(), field.getIndex() + offset);
-							}
-						}
-						++i;
-						offset += c.getRowType().getFieldCount();
-					}
-					final RexNode c =
-							rexBuilder.makeCorrel(builder.uniquify().build(), correlId);
-					return Pair.of(c, fields.build());
-				}
-			}
-		}
-
-		/**
-		 * Creates an expression with which to reference the expression whose
-		 * offset in its from-list is {@code offset}.
-		 */
-		RexNode lookup(
-				int offset,
-				LookupContext lookupContext) {
-			Pair<RelNode, Integer> pair = lookupContext.findRel(offset);
-			return rexBuilder.makeRangeReference(
-					pair.left.getRowType(),
-					pair.right,
-					false);
-		}
-
-		RelDataTypeField getRootField(RexInputRef inputRef) {
-			if (inputs == null) {
-				return null;
-			}
-			int fieldOffset = inputRef.getIndex();
-			for (RelNode input : inputs) {
-				RelDataType rowType = input.getRowType();
-				if (rowType == null) {
-					// TODO:  remove this once leastRestrictive
-					// is correctly implemented
-					return null;
-				}
-				if (fieldOffset < rowType.getFieldCount()) {
-					return rowType.getFieldList().get(fieldOffset);
-				}
-				fieldOffset -= rowType.getFieldCount();
-			}
-			throw new AssertionError();
-		}
-
-		public void flatten(
-				List<RelNode> rels,
-				int systemFieldCount,
-				int[] start,
-				List<Pair<RelNode, Integer>> relOffsetList) {
-			for (RelNode rel : rels) {
-				if (leaves.contains(rel) || rel instanceof LogicalMatch) {
-					relOffsetList.add(
-							Pair.of(rel, start[0]));
-					start[0] += rel.getRowType().getFieldCount();
-				} else {
-					if (rel instanceof LogicalJoin
-							|| rel instanceof LogicalAggregate) {
-						start[0] += systemFieldCount;
-					}
-					flatten(
-							rel.getInputs(),
-							systemFieldCount,
-							start,
-							relOffsetList);
-				}
-			}
-		}
-
-		void registerSubQuery(SqlNode node, RelOptUtil.Logic logic) {
-			for (SubQuery subQuery : subQueryList) {
-				if (node.equalsDeep(subQuery.node, Litmus.IGNORE)) {
-					return;
-				}
-			}
-			subQueryList.add(new SubQuery(node, logic));
-		}
-
-		SubQuery getSubQuery(SqlNode expr) {
-			for (SubQuery subQuery : subQueryList) {
-				if (expr.equalsDeep(subQuery.node, Litmus.IGNORE)) {
-					return subQuery;
-				}
-			}
-
-			return null;
-		}
-
-		ImmutableList<RelNode> retrieveCursors() {
-			try {
-				return ImmutableList.copyOf(cursors);
-			} finally {
-				cursors.clear();
-			}
-		}
-
-		public RexNode convertExpression(SqlNode expr) {
-			// If we're in aggregation mode and this is an expression in the
-			// GROUP BY clause, return a reference to the field.
-			if (agg != null) {
-				final SqlNode expandedGroupExpr = validator.expand(expr, scope);
-				final int ref = agg.lookupGroupExpr(expandedGroupExpr);
-				if (ref >= 0) {
-					return rexBuilder.makeInputRef(root, ref);
-				}
-				if (expr instanceof SqlCall) {
-					final RexNode rex = agg.lookupAggregates((SqlCall) expr);
-					if (rex != null) {
-						return rex;
-					}
-				}
-			}
-
-			// Allow the derived class chance to override the standard
-			// behavior for special kinds of expressions.
-			RexNode rex = convertExtendedExpression(expr, this);
-			if (rex != null) {
-				return rex;
-			}
-
-			// Sub-queries and OVER expressions are not like ordinary
-			// expressions.
-			final SqlKind kind = expr.getKind();
-			final SubQuery subQuery;
-			if (!config.isExpand()) {
-				final SqlCall call;
-				final SqlNode query;
-				final RelRoot root;
-				switch (kind) {
-					case IN:
-					case NOT_IN:
-					case SOME:
-					case ALL:
-						call = (SqlCall) expr;
-						query = call.operand(1);
-						if (!(query instanceof SqlNodeList)) {
-							root = convertQueryRecursive(query, false, null);
-							final SqlNode operand = call.operand(0);
-							List<SqlNode> nodes;
-							switch (operand.getKind()) {
-								case ROW:
-									nodes = ((SqlCall) operand).getOperandList();
-									break;
-								default:
-									nodes = ImmutableList.of(operand);
-							}
-							final ImmutableList.Builder<RexNode> builder =
-									ImmutableList.builder();
-							for (SqlNode node : nodes) {
-								builder.add(convertExpression(node));
-							}
-							final ImmutableList<RexNode> list = builder.build();
-							switch (kind) {
-								case IN:
-									return RexSubQuery.in(root.rel, list);
-								case NOT_IN:
-									return rexBuilder.makeCall(SqlStdOperatorTable.NOT,
-											RexSubQuery.in(root.rel, list));
-								case SOME:
-									return RexSubQuery.some(root.rel, list,
-											(SqlQuantifyOperator) call.getOperator());
-								case ALL:
-									return rexBuilder.makeCall(SqlStdOperatorTable.NOT,
-											RexSubQuery.some(root.rel, list,
-													negate((SqlQuantifyOperator) call.getOperator())));
-								default:
-									throw new AssertionError(kind);
-							}
-						}
-						break;
-
-					case EXISTS:
-						call = (SqlCall) expr;
-						query = Iterables.getOnlyElement(call.getOperandList());
-						root = convertQueryRecursive(query, false, null);
-						RelNode rel = root.rel;
-						while (rel instanceof Project
-								|| rel instanceof Sort
-								&& ((Sort) rel).fetch == null
-								&& ((Sort) rel).offset == null) {
-							rel = ((SingleRel) rel).getInput();
-						}
-						return RexSubQuery.exists(rel);
-
-					case SCALAR_QUERY:
-						call = (SqlCall) expr;
-						query = Iterables.getOnlyElement(call.getOperandList());
-						root = convertQueryRecursive(query, false, null);
-						return RexSubQuery.scalar(root.rel);
-				}
-			}
-
-			switch (kind) {
-				case SOME:
-				case ALL:
-					if (config.isExpand()) {
-						throw new RuntimeException(kind
-								+ " is only supported if expand = false");
-					}
-					// fall through
-				case CURSOR:
-				case IN:
-				case NOT_IN:
-					subQuery = Objects.requireNonNull(getSubQuery(expr));
-					rex = Objects.requireNonNull(subQuery.expr);
-					return StandardConvertletTable.castToValidatedType(expr, rex,
-							validator, rexBuilder);
-
-				case SELECT:
-				case EXISTS:
-				case SCALAR_QUERY:
-					subQuery = getSubQuery(expr);
-					assert subQuery != null;
-					rex = subQuery.expr;
-					assert rex != null : "rex != null";
-
-					if (((kind == SqlKind.SCALAR_QUERY)
-							|| (kind == SqlKind.EXISTS))
-							&& isConvertedSubq(rex)) {
-						// scalar sub-query or EXISTS has been converted to a
-						// constant
-						return rex;
-					}
-
-					// The indicator column is the last field of the sub-query.
-					RexNode fieldAccess =
-							rexBuilder.makeFieldAccess(
-									rex,
-									rex.getType().getFieldCount() - 1);
-
-					// The indicator column will be nullable if it comes from
-					// the null-generating side of the join. For EXISTS, add an
-					// "IS TRUE" check so that the result is "BOOLEAN NOT NULL".
-					if (fieldAccess.getType().isNullable()
-							&& kind == SqlKind.EXISTS) {
-						fieldAccess =
-								rexBuilder.makeCall(
-										SqlStdOperatorTable.IS_NOT_NULL,
-										fieldAccess);
-					}
-					return fieldAccess;
-
-				case OVER:
-					return convertOver(this, expr);
-
-				default:
-					// fall through
-			}
-
-			// Apply standard conversions.
-			rex = expr.accept(this);
-			return Objects.requireNonNull(rex);
-		}
-
-		/**
-		 * Converts an item in an ORDER BY clause inside a window (OVER) clause,
-		 * extracting DESC, NULLS LAST and NULLS FIRST flags first.
-		 */
-		public RexFieldCollation convertSortExpression(SqlNode expr,
-		                                               RelFieldCollation.Direction direction,
-		                                               RelFieldCollation.NullDirection nullDirection) {
-			switch (expr.getKind()) {
-				case DESCENDING:
-					return convertSortExpression(((SqlCall) expr).operand(0),
-							RelFieldCollation.Direction.DESCENDING, nullDirection);
-				case NULLS_LAST:
-					return convertSortExpression(((SqlCall) expr).operand(0),
-							direction, RelFieldCollation.NullDirection.LAST);
-				case NULLS_FIRST:
-					return convertSortExpression(((SqlCall) expr).operand(0),
-							direction, RelFieldCollation.NullDirection.FIRST);
-				default:
-					final Set<SqlKind> flags = EnumSet.noneOf(SqlKind.class);
-					switch (direction) {
-						case DESCENDING:
-							flags.add(SqlKind.DESCENDING);
-					}
-					switch (nullDirection) {
-						case UNSPECIFIED:
-							final RelFieldCollation.NullDirection nullDefaultDirection =
-									validator.getDefaultNullCollation().last(desc(direction))
-											? RelFieldCollation.NullDirection.LAST
-											: RelFieldCollation.NullDirection.FIRST;
-							if (nullDefaultDirection != direction.defaultNullDirection()) {
-								SqlKind nullDirectionSqlKind =
-										validator.getDefaultNullCollation().last(desc(direction))
-												? SqlKind.NULLS_LAST
-												: SqlKind.NULLS_FIRST;
-								flags.add(nullDirectionSqlKind);
-							}
-							break;
-						case FIRST:
-							flags.add(SqlKind.NULLS_FIRST);
-							break;
-						case LAST:
-							flags.add(SqlKind.NULLS_LAST);
-							break;
-					}
-					return new RexFieldCollation(convertExpression(expr), flags);
-			}
-		}
-
-		/**
-		 * Determines whether a RexNode corresponds to a sub-query that's been
-		 * converted to a constant.
-		 *
-		 * @param rex the expression to be examined
-		 * @return true if the expression is a dynamic parameter, a literal, or
-		 * a literal that is being cast
-		 */
-		private boolean isConvertedSubq(RexNode rex) {
-			if ((rex instanceof RexLiteral)
-					|| (rex instanceof RexDynamicParam)) {
-				return true;
-			}
-			if (rex instanceof RexCall) {
-				RexCall call = (RexCall) rex;
-				if (call.getOperator() == SqlStdOperatorTable.CAST) {
-					RexNode operand = call.getOperands().get(0);
-					if (operand instanceof RexLiteral) {
-						return true;
-					}
-				}
-			}
-			return false;
-		}
-
-		public int getGroupCount() {
-			if (agg != null) {
-				return agg.groupExprs.size();
-			}
-			if (window != null) {
-				return window.isAlwaysNonEmpty() ? 1 : 0;
-			}
-			return -1;
-		}
-
-		public RexBuilder getRexBuilder() {
-			return rexBuilder;
-		}
-
-		public RexRangeRef getSubQueryExpr(SqlCall call) {
-			final SubQuery subQuery = getSubQuery(call);
-			assert subQuery != null;
-			return (RexRangeRef) subQuery.expr;
-		}
-
-		public RelDataTypeFactory getTypeFactory() {
-			return typeFactory;
-		}
-
-		public InitializerExpressionFactory getInitializerExpressionFactory() {
-			return initializerExpressionFactory;
-		}
-
-		public SqlValidator getValidator() {
-			return validator;
-		}
-
-		public RexNode convertLiteral(SqlLiteral literal) {
-			return exprConverter.convertLiteral(this, literal);
-		}
-
-		public RexNode convertInterval(SqlIntervalQualifier intervalQualifier) {
-			return exprConverter.convertInterval(this, intervalQualifier);
-		}
-
-		public RexNode visit(SqlLiteral literal) {
-			return exprConverter.convertLiteral(this, literal);
-		}
-
-		public RexNode visit(SqlCall call) {
-			if (agg != null) {
-				final SqlOperator op = call.getOperator();
-				if (window == null
-						&& (op.isAggregator() || op.getKind() == SqlKind.FILTER)) {
-					return agg.lookupAggregates(call);
-				}
-			}
-			return exprConverter.convertCall(this,
-					new SqlCallBinding(validator, scope, call).permutedCall());
-		}
-
-		public RexNode visit(SqlNodeList nodeList) {
-			throw new UnsupportedOperationException();
-		}
-
-		public RexNode visit(SqlIdentifier id) {
-			return convertIdentifier(this, id);
-		}
-
-		public RexNode visit(SqlDataTypeSpec type) {
-			throw new UnsupportedOperationException();
-		}
-
-		public RexNode visit(SqlDynamicParam param) {
-			return convertDynamicParam(param);
-		}
-
-		public RexNode visit(SqlIntervalQualifier intervalQualifier) {
-			return convertInterval(intervalQualifier);
-		}
-
-		public List<SqlMonotonicity> getColumnMonotonicities() {
-			return columnMonotonicities;
-		}
-
-	}
-
-	private SqlQuantifyOperator negate(SqlQuantifyOperator operator) {
-		assert operator.kind == SqlKind.ALL;
-		return SqlStdOperatorTable.some(operator.comparisonKind.negateNullSafe());
-	}
-
-	/** Deferred lookup. */
-	private static class DeferredLookup {
-		Blackboard bb;
-		String originalRelName;
-
-		DeferredLookup(
-				Blackboard bb,
-				String originalRelName) {
-			this.bb = bb;
-			this.originalRelName = originalRelName;
-		}
-
-		public RexFieldAccess getFieldAccess(CorrelationId name) {
-			return (RexFieldAccess) bb.mapCorrelateToRex.get(name);
-		}
-
-		public String getOriginalRelName() {
-			return originalRelName;
-		}
-	}
-
-	/**
-	 * A default implementation of SubQueryConverter that does no conversion.
-	 */
-	private class NoOpSubQueryConverter implements SubQueryConverter {
-		public boolean canConvertSubQuery() {
-			return false;
-		}
-
-		public RexNode convertSubQuery(
-				SqlCall subQuery,
-				SqlToRelConverter parentConverter,
-				boolean isExists,
-				boolean isExplain) {
-			throw new IllegalArgumentException();
-		}
-	}
-
-	/**
-	 * Converts expressions to aggregates.
-	 *
-	 * <p>Consider the expression
-	 *
-	 * <blockquote>
-	 * {@code SELECT deptno, SUM(2 * sal) FROM emp GROUP BY deptno}
-	 * </blockquote>
-	 *
-	 * <p>Then:
-	 *
-	 * <ul>
-	 * <li>groupExprs = {SqlIdentifier(deptno)}</li>
-	 * <li>convertedInputExprs = {RexInputRef(deptno), 2 *
-	 * RefInputRef(sal)}</li>
-	 * <li>inputRefs = {RefInputRef(#0), RexInputRef(#1)}</li>
-	 * <li>aggCalls = {AggCall(SUM, {1})}</li>
-	 * </ul>
-	 */
-	protected class AggConverter implements SqlVisitor<Void> {
-		private final Blackboard bb;
-		public final AggregatingSelectScope aggregatingSelectScope;
-
-		private final Map<String, String> nameMap = new HashMap<>();
-
-		/**
-		 * The group-by expressions, in {@link SqlNode} format.
-		 */
-		private final SqlNodeList groupExprs =
-				new SqlNodeList(SqlParserPos.ZERO);
-
-		/**
-		 * The auxiliary group-by expressions.
-		 */
-		private final Map<SqlNode, Ord<AuxiliaryConverter>> auxiliaryGroupExprs =
-				new HashMap<>();
-
-		/**
-		 * Input expressions for the group columns and aggregates, in
-		 * {@link RexNode} format. The first elements of the list correspond to the
-		 * elements in {@link #groupExprs}; the remaining elements are for
-		 * aggregates. The right field of each pair is the name of the expression,
-		 * where the expressions are simple mappings to input fields.
-		 */
-		private final List<Pair<RexNode, String>> convertedInputExprs =
-				new ArrayList<>();
-
-		/** Expressions to be evaluated as rows are being placed into the
-		 * aggregate's hash table. This is when group functions such as TUMBLE
-		 * cause rows to be expanded. */
-
-		private final List<AggregateCall> aggCalls = new ArrayList<>();
-		private final Map<SqlNode, RexNode> aggMapping = new HashMap<>();
-		private final Map<AggregateCall, RexNode> aggCallMapping =
-				new HashMap<>();
-
-		/** Are we directly inside a windowed aggregate? */
-		private boolean inOver = false;
-
-		/**
-		 * Creates an AggConverter.
-		 *
-		 * <p>The <code>select</code> parameter provides enough context to name
-		 * aggregate calls which are top-level select list items.
-		 *
-		 * @param bb     Blackboard
-		 * @param select Query being translated; provides context to give
-		 */
-		public AggConverter(Blackboard bb, SqlSelect select) {
-			this.bb = bb;
-			this.aggregatingSelectScope =
-					(AggregatingSelectScope) bb.getValidator().getSelectScope(select);
-
-			// Collect all expressions used in the select list so that aggregate
-			// calls can be named correctly.
-			final SqlNodeList selectList = select.getSelectList();
-			for (int i = 0; i < selectList.size(); i++) {
-				SqlNode selectItem = selectList.get(i);
-				String name = null;
-				if (SqlUtil.isCallTo(
-						selectItem,
-						SqlStdOperatorTable.AS)) {
-					final SqlCall call = (SqlCall) selectItem;
-					selectItem = call.operand(0);
-					name = call.operand(1).toString();
-				}
-				if (name == null) {
-					name = validator.deriveAlias(selectItem, i);
-				}
-				nameMap.put(selectItem.toString(), name);
-			}
-		}
-
-		public int addGroupExpr(SqlNode expr) {
-			int ref = lookupGroupExpr(expr);
-			if (ref >= 0) {
-				return ref;
-			}
-			final int index = groupExprs.size();
-			groupExprs.add(expr);
-			String name = nameMap.get(expr.toString());
-			RexNode convExpr = bb.convertExpression(expr);
-			addExpr(convExpr, name);
-
-			if (expr instanceof SqlCall) {
-				SqlCall call = (SqlCall) expr;
-				for (Pair<SqlNode, AuxiliaryConverter> p
-						: SqlStdOperatorTable.convertGroupToAuxiliaryCalls(call)) {
-					addAuxiliaryGroupExpr(p.left, index, p.right);
-				}
-			}
-
-			return index;
-		}
-
-		void addAuxiliaryGroupExpr(SqlNode node, int index,
-		                           AuxiliaryConverter converter) {
-			for (SqlNode node2 : auxiliaryGroupExprs.keySet()) {
-				if (node2.equalsDeep(node, Litmus.IGNORE)) {
-					return;
-				}
-			}
-			auxiliaryGroupExprs.put(node, Ord.of(index, converter));
-		}
-
-		/**
-		 * Adds an expression, deducing an appropriate name if possible.
-		 *
-		 * @param expr Expression
-		 * @param name Suggested name
-		 */
-		private void addExpr(RexNode expr, String name) {
-			if ((name == null) && (expr instanceof RexInputRef)) {
-				final int i = ((RexInputRef) expr).getIndex();
-				name = bb.root.getRowType().getFieldList().get(i).getName();
-			}
-			if (Pair.right(convertedInputExprs).contains(name)) {
-				// In case like 'SELECT ... GROUP BY x, y, x', don't add
-				// name 'x' twice.
-				name = null;
-			}
-			convertedInputExprs.add(Pair.of(expr, name));
-		}
-
-		public Void visit(SqlIdentifier id) {
-			return null;
-		}
-
-		public Void visit(SqlNodeList nodeList) {
-			for (int i = 0; i < nodeList.size(); i++) {
-				nodeList.get(i).accept(this);
-			}
-			return null;
-		}
-
-		public Void visit(SqlLiteral lit) {
-			return null;
-		}
-
-		public Void visit(SqlDataTypeSpec type) {
-			return null;
-		}
-
-		public Void visit(SqlDynamicParam param) {
-			return null;
-		}
-
-		public Void visit(SqlIntervalQualifier intervalQualifier) {
-			return null;
-		}
-
-		public Void visit(SqlCall call) {
-			switch (call.getKind()) {
-				case FILTER:
-					translateAgg((SqlCall) call.operand(0), call.operand(1), call);
-					return null;
-				case SELECT:
-					// rchen 2006-10-17:
-					// for now do not detect aggregates in sub-queries.
-					return null;
-			}
-			final boolean prevInOver = inOver;
-			// Ignore window aggregates and ranking functions (associated with OVER
-			// operator). However, do not ignore nested window aggregates.
-			if (call.getOperator().getKind() == SqlKind.OVER) {
-				// Track aggregate nesting levels only within an OVER operator.
-				List<SqlNode> operandList = call.getOperandList();
-				assert operandList.size() == 2;
-
-				// Ignore the top level window aggregates and ranking functions
-				// positioned as the first operand of a OVER operator
-				inOver = true;
-				operandList.get(0).accept(this);
-
-				// Normal translation for the second operand of a OVER operator
-				inOver = false;
-				operandList.get(1).accept(this);
-				return null;
-			}
-
-			// Do not translate the top level window aggregate. Only do so for
-			// nested aggregates, if present
-			if (call.getOperator().isAggregator()) {
-				if (inOver) {
-					// Add the parent aggregate level before visiting its children
-					inOver = false;
-				} else {
-					// We're beyond the one ignored level
-					translateAgg(call, null, call);
-					return null;
-				}
-			}
-			for (SqlNode operand : call.getOperandList()) {
-				// Operands are occasionally null, e.g. switched CASE arg 0.
-				if (operand != null) {
-					operand.accept(this);
-				}
-			}
-			// Remove the parent aggregate level after visiting its children
-			inOver = prevInOver;
-			return null;
-		}
-
-		private void translateAgg(SqlCall call, SqlNode filter, SqlCall outerCall) {
-			assert bb.agg == this;
-			final List<Integer> args = new ArrayList<>();
-			int filterArg = -1;
-			final List<RelDataType> argTypes =
-					call.getOperator() instanceof SqlCountAggFunction
-							? new ArrayList<RelDataType>(call.getOperandList().size())
-							: null;
-			try {
-				// switch out of agg mode
-				bb.agg = null;
-				for (SqlNode operand : call.getOperandList()) {
-
-					// special case for COUNT(*):  delete the *
-					if (operand instanceof SqlIdentifier) {
-						SqlIdentifier id = (SqlIdentifier) operand;
-						if (id.isStar()) {
-							assert call.operandCount() == 1;
-							assert args.isEmpty();
-							break;
-						}
-					}
-					RexNode convertedExpr = bb.convertExpression(operand);
-					assert convertedExpr != null;
-					if (argTypes != null) {
-						argTypes.add(convertedExpr.getType());
-					}
-					args.add(lookupOrCreateGroupExpr(convertedExpr));
-				}
-
-				if (filter != null) {
-					RexNode convertedExpr = bb.convertExpression(filter);
-					assert convertedExpr != null;
-					if (convertedExpr.getType().isNullable()) {
-						convertedExpr =
-								rexBuilder.makeCall(SqlStdOperatorTable.IS_TRUE, convertedExpr);
-					}
-					filterArg = lookupOrCreateGroupExpr(convertedExpr);
-				}
-			} finally {
-				// switch back into agg mode
-				bb.agg = this;
-			}
-
-			SqlAggFunction aggFunction =
-					(SqlAggFunction) call.getOperator();
-			final RelDataType type = validator.deriveType(bb.scope, call);
-			boolean distinct = false;
-			SqlLiteral quantifier = call.getFunctionQuantifier();
-			if ((null != quantifier)
-					&& (quantifier.getValue() == SqlSelectKeyword.DISTINCT)) {
-				distinct = true;
-			}
-			boolean approximate = false;
-			if (aggFunction == SqlStdOperatorTable.APPROX_COUNT_DISTINCT) {
-				aggFunction = SqlStdOperatorTable.COUNT;
-				distinct = true;
-				approximate = true;
-			}
-			final AggregateCall aggCall =
-					AggregateCall.create(
-							aggFunction,
-							distinct,
-							approximate,
-							args,
-							filterArg,
-							type,
-							nameMap.get(outerCall.toString()));
-			final AggregatingSelectScope.Resolved r =
-					aggregatingSelectScope.resolved.get();
-			RexNode rex =
-					rexBuilder.addAggCall(
-							aggCall,
-							groupExprs.size(),
-							false,
-							aggCalls,
-							aggCallMapping,
-							argTypes);
-			aggMapping.put(outerCall, rex);
-		}
-
-		private int lookupOrCreateGroupExpr(RexNode expr) {
-			int index = 0;
-			for (RexNode convertedInputExpr : Pair.left(convertedInputExprs)) {
-				if (expr.toString().equals(convertedInputExpr.toString())) {
-					return index;
-				}
-				++index;
-			}
-
-			// not found -- add it
-			addExpr(expr, null);
-			return index;
-		}
-
-		/**
-		 * If an expression is structurally identical to one of the group-by
-		 * expressions, returns a reference to the expression, otherwise returns
-		 * null.
-		 */
-		public int lookupGroupExpr(SqlNode expr) {
-			for (int i = 0; i < groupExprs.size(); i++) {
-				SqlNode groupExpr = groupExprs.get(i);
-				if (expr.equalsDeep(groupExpr, Litmus.IGNORE)) {
-					return i;
-				}
-			}
-			return -1;
-		}
-
-		public RexNode lookupAggregates(SqlCall call) {
-			// assert call.getOperator().isAggregator();
-			assert bb.agg == this;
-
-			for (Map.Entry<SqlNode, Ord<AuxiliaryConverter>> e
-					: auxiliaryGroupExprs.entrySet()) {
-				if (call.equalsDeep(e.getKey(), Litmus.IGNORE)) {
-					AuxiliaryConverter converter = e.getValue().e;
-					final int groupOrdinal = e.getValue().i;
-					return converter.convert(rexBuilder,
-							convertedInputExprs.get(groupOrdinal).left,
-							rexBuilder.makeInputRef(bb.root, groupOrdinal));
-				}
-			}
-
-			return aggMapping.get(call);
-		}
-
-		public List<Pair<RexNode, String>> getPreExprs() {
-			return convertedInputExprs;
-		}
-
-		public List<AggregateCall> getAggCalls() {
-			return aggCalls;
-		}
-
-		public RelDataTypeFactory getTypeFactory() {
-			return typeFactory;
-		}
-	}
-
-	/**
-	 * Context to find a relational expression to a field offset.
-	 */
-	private static class LookupContext {
-		private final List<Pair<RelNode, Integer>> relOffsetList =
-				new ArrayList<>();
-
-		/**
-		 * Creates a LookupContext with multiple input relational expressions.
-		 *
-		 * @param bb               Context for translating this sub-query
-		 * @param rels             Relational expressions
-		 * @param systemFieldCount Number of system fields
-		 */
-		LookupContext(Blackboard bb, List<RelNode> rels, int systemFieldCount) {
-			bb.flatten(rels, systemFieldCount, new int[]{0}, relOffsetList);
-		}
-
-		/**
-		 * Returns the relational expression with a given offset, and the
-		 * ordinal in the combined row of its first field.
-		 *
-		 * <p>For example, in {@code Emp JOIN Dept}, findRel(1) returns the
-		 * relational expression for {@code Dept} and offset 6 (because
-		 * {@code Emp} has 6 fields, therefore the first field of {@code Dept}
-		 * is field 6.
-		 *
-		 * @param offset Offset of relational expression in FROM clause
-		 * @return Relational expression and the ordinal of its first field
-		 */
-		Pair<RelNode, Integer> findRel(int offset) {
-			return relOffsetList.get(offset);
-		}
-	}
-
-	/**
-	 * Shuttle which walks over a tree of {@link RexNode}s and applies 'over' to
-	 * all agg functions.
-	 *
-	 * <p>This is necessary because the returned expression is not necessarily a
-	 * call to an agg function. For example,
-	 *
-	 * <blockquote><code>AVG(x)</code></blockquote>
-	 *
-	 * <p>becomes
-	 *
-	 * <blockquote><code>SUM(x) / COUNT(x)</code></blockquote>
-	 *
-	 * <p>Any aggregate functions are converted to calls to the internal <code>
-	 * $Histogram</code> aggregation function and accessors such as <code>
-	 * $HistogramMin</code>; for example,
-	 *
-	 * <blockquote><code>MIN(x), MAX(x)</code></blockquote>
-	 *
-	 * <p>are converted to
-	 *
-	 * <blockquote><code>$HistogramMin($Histogram(x)),
-	 * $HistogramMax($Histogram(x))</code></blockquote>
-	 *
-	 * <p>Common sub-expression elimination will ensure that only one histogram is
-	 * computed.
-	 */
-	private class HistogramShuttle extends RexShuttle {
-		/**
-		 * Whether to convert calls to MIN(x) to HISTOGRAM_MIN(HISTOGRAM(x)).
-		 * Histograms allow rolling computation, but require more space.
-		 */
-		static final boolean ENABLE_HISTOGRAM_AGG = false;
-
-		private final List<RexNode> partitionKeys;
-		private final ImmutableList<RexFieldCollation> orderKeys;
-		private final RexWindowBound lowerBound;
-		private final RexWindowBound upperBound;
-		private final SqlWindow window;
-		private final boolean distinct;
-
-		HistogramShuttle(
-				List<RexNode> partitionKeys,
-				ImmutableList<RexFieldCollation> orderKeys,
-				RexWindowBound lowerBound, RexWindowBound upperBound,
-				SqlWindow window,
-				boolean distinct) {
-			this.partitionKeys = partitionKeys;
-			this.orderKeys = orderKeys;
-			this.lowerBound = lowerBound;
-			this.upperBound = upperBound;
-			this.window = window;
-			this.distinct = distinct;
-		}
-
-		public RexNode visitCall(RexCall call) {
-			final SqlOperator op = call.getOperator();
-			if (!(op instanceof SqlAggFunction)) {
-				return super.visitCall(call);
-			}
-			final SqlAggFunction aggOp = (SqlAggFunction) op;
-			final RelDataType type = call.getType();
-			List<RexNode> exprs = call.getOperands();
-
-			SqlFunction histogramOp = !ENABLE_HISTOGRAM_AGG
-					? null
-					: getHistogramOp(aggOp);
-
-			if (histogramOp != null) {
-				final RelDataType histogramType = computeHistogramType(type);
-
-				// For DECIMAL, since it's already represented as a bigint we
-				// want to do a reinterpretCast instead of a cast to avoid
-				// losing any precision.
-				boolean reinterpretCast =
-						type.getSqlTypeName() == SqlTypeName.DECIMAL;
-
-				// Replace original expression with CAST of not one
-				// of the supported types
-				if (histogramType != type) {
-					exprs = new ArrayList<>(exprs);
-					exprs.set(
-							0,
-							reinterpretCast
-									? rexBuilder.makeReinterpretCast(histogramType, exprs.get(0),
-									rexBuilder.makeLiteral(false))
-									: rexBuilder.makeCast(histogramType, exprs.get(0)));
-				}
-
-				RexCallBinding bind =
-						new RexCallBinding(
-								rexBuilder.getTypeFactory(),
-								SqlStdOperatorTable.HISTOGRAM_AGG,
-								exprs,
-								ImmutableList.of());
-
-				RexNode over =
-						rexBuilder.makeOver(
-								SqlStdOperatorTable.HISTOGRAM_AGG
-										.inferReturnType(bind),
-								SqlStdOperatorTable.HISTOGRAM_AGG,
-								exprs,
-								partitionKeys,
-								orderKeys,
-								lowerBound,
-								upperBound,
-								window.isRows(),
-								window.isAllowPartial(),
-								false,
-								distinct);
-
-				RexNode histogramCall =
-						rexBuilder.makeCall(
-								histogramType,
-								histogramOp,
-								ImmutableList.of(over));
-
-				// If needed, post Cast result back to original
-				// type.
-				if (histogramType != type) {
-					if (reinterpretCast) {
-						histogramCall =
-								rexBuilder.makeReinterpretCast(
-										type,
-										histogramCall,
-										rexBuilder.makeLiteral(false));
-					} else {
-						histogramCall =
-								rexBuilder.makeCast(type, histogramCall);
-					}
-				}
-
-				return histogramCall;
-			} else {
-				boolean needSum0 = aggOp == SqlStdOperatorTable.SUM
-						&& type.isNullable();
-				SqlAggFunction aggOpToUse =
-						needSum0 ? SqlStdOperatorTable.SUM0
-								: aggOp;
-				return rexBuilder.makeOver(
-						type,
-						aggOpToUse,
-						exprs,
-						partitionKeys,
-						orderKeys,
-						lowerBound,
-						upperBound,
-						window.isRows(),
-						window.isAllowPartial(),
-						needSum0,
-						distinct);
-			}
-		}
-
-		/**
-		 * Returns the histogram operator corresponding to a given aggregate
-		 * function.
-		 *
-		 * <p>For example, <code>getHistogramOp
-		 *({@link SqlStdOperatorTable#MIN}}</code> returns
-		 * {@link SqlStdOperatorTable#HISTOGRAM_MIN}.
-		 *
-		 * @param aggFunction An aggregate function
-		 * @return Its histogram function, or null
-		 */
-		SqlFunction getHistogramOp(SqlAggFunction aggFunction) {
-			if (aggFunction == SqlStdOperatorTable.MIN) {
-				return SqlStdOperatorTable.HISTOGRAM_MIN;
-			} else if (aggFunction == SqlStdOperatorTable.MAX) {
-				return SqlStdOperatorTable.HISTOGRAM_MAX;
-			} else if (aggFunction == SqlStdOperatorTable.FIRST_VALUE) {
-				return SqlStdOperatorTable.HISTOGRAM_FIRST_VALUE;
-			} else if (aggFunction == SqlStdOperatorTable.LAST_VALUE) {
-				return SqlStdOperatorTable.HISTOGRAM_LAST_VALUE;
-			} else {
-				return null;
-			}
-		}
-
-		/**
-		 * Returns the type for a histogram function. It is either the actual
-		 * type or an an approximation to it.
-		 */
-		private RelDataType computeHistogramType(RelDataType type) {
-			if (SqlTypeUtil.isExactNumeric(type)
-					&& type.getSqlTypeName() != SqlTypeName.BIGINT) {
-				return typeFactory.createSqlType(SqlTypeName.BIGINT);
-			} else if (SqlTypeUtil.isApproximateNumeric(type)
-					&& type.getSqlTypeName() != SqlTypeName.DOUBLE) {
-				return typeFactory.createSqlType(SqlTypeName.DOUBLE);
-			} else {
-				return type;
-			}
-		}
-	}
-
-	/** A sub-query, whether it needs to be translated using 2- or 3-valued
-	 * logic. */
-	private static class SubQuery {
-		final SqlNode node;
-		final RelOptUtil.Logic logic;
-		RexNode expr;
-
-		private SubQuery(SqlNode node, RelOptUtil.Logic logic) {
-			this.node = node;
-			this.logic = logic;
-		}
-	}
-
-	/**
-	 * Visitor that collects all aggregate functions in a {@link SqlNode} tree.
-	 */
-	private static class AggregateFinder extends SqlBasicVisitor<Void> {
-		final SqlNodeList list = new SqlNodeList(SqlParserPos.ZERO);
-		final SqlNodeList filterList = new SqlNodeList(SqlParserPos.ZERO);
-
-		@Override public Void visit(SqlCall call) {
-			// ignore window aggregates and ranking functions (associated with OVER operator)
-			if (call.getOperator().getKind() == SqlKind.OVER) {
-				return null;
-			}
-
-			if (call.getOperator().getKind() == SqlKind.FILTER) {
-				// the WHERE in a FILTER must be tracked too so we can call replaceSubQueries on it.
-				// see https://issues.apache.org/jira/browse/CALCITE-1910
-				final SqlNode aggCall = call.getOperandList().get(0);
-				final SqlNode whereCall = call.getOperandList().get(1);
-				list.add(aggCall);
-				filterList.add(whereCall);
-				return null;
-			}
-
-			if (call.getOperator().isAggregator()) {
-				list.add(call);
-				return null;
-			}
-
-			// Don't traverse into sub-queries, even if they contain aggregate
-			// functions.
-			if (call instanceof SqlSelect) {
-				return null;
-			}
-
-			return call.getOperator().acceptCall(this, call);
-		}
-	}
-
-	/** Use of a row as a correlating variable by a given relational
-	 * expression. */
-	private static class CorrelationUse {
-		private final CorrelationId id;
-		private final ImmutableBitSet requiredColumns;
-		/** The relational expression that uses the variable. */
-		private final RelNode r;
-
-		CorrelationUse(CorrelationId id, ImmutableBitSet requiredColumns,
-		               RelNode r) {
-			this.id = id;
-			this.requiredColumns = requiredColumns;
-			this.r = r;
-		}
-	}
-
-	/** Creates a builder for a {@link Config}. */
-	public static ConfigBuilder configBuilder() {
-		return new ConfigBuilder();
-	}
-
-	/**
-	 * Interface to define the configuration for a SqlToRelConverter.
-	 * Provides methods to set each configuration option.
-	 *
-	 * @see ConfigBuilder
-	 * @see SqlToRelConverter#configBuilder()
-	 */
-	public interface Config {
-		/** Default configuration. */
-		Config DEFAULT = configBuilder().build();
-
-		/** Returns the {@code convertTableAccess} option. Controls whether table
-		 * access references are converted to physical rels immediately. The
-		 * optimizer doesn't like leaf rels to have {@link Convention#NONE}.
-		 * However, if we are doing further conversion passes (e.g.
-		 * {@link RelStructuredTypeFlattener}), then we may need to defer
-		 * conversion. */
-		boolean isConvertTableAccess();
-
-		/** Returns the {@code decorrelationEnabled} option. Controls whether to
-		 * disable sub-query decorrelation when needed. e.g. if outer joins are not
-		 * supported. */
-		boolean isDecorrelationEnabled();
-
-		/** Returns the {@code trimUnusedFields} option. Controls whether to trim
-		 * unused fields as part of the conversion process. */
-		boolean isTrimUnusedFields();
-
-		/** Returns the {@code createValuesRel} option. Controls whether instances
-		 * of {@link org.apache.calcite.rel.logical.LogicalValues} are generated.
-		 * These may not be supported by all physical implementations. */
-		boolean isCreateValuesRel();
-
-		/** Returns the {@code explain} option. Describes whether the current
-		 * statement is part of an EXPLAIN PLAN statement. */
-		boolean isExplain();
-
-		/** Returns the {@code expand} option. Controls whether to expand
-		 * sub-queries. If false, each sub-query becomes a
-		 * {@link org.apache.calcite.rex.RexSubQuery}. */
-		boolean isExpand();
-
-		/** Returns the {@code inSubQueryThreshold} option,
-		 * default {@link #DEFAULT_IN_SUB_QUERY_THRESHOLD}. Controls the list size
-		 * threshold under which {@link #convertInToOr} is used. Lists of this size
-		 * or greater will instead be converted to use a join against an inline
-		 * table ({@link org.apache.calcite.rel.logical.LogicalValues}) rather than
-		 * a predicate. A threshold of 0 forces usage of an inline table in all
-		 * cases; a threshold of {@link Integer#MAX_VALUE} forces usage of OR in all
-		 * cases. */
-		int getInSubQueryThreshold();
-
-		/** Returns the factory to create {@link RelBuilder}, never null. Default is
-		 * {@link RelFactories#LOGICAL_BUILDER}. */
-		RelBuilderFactory getRelBuilderFactory();
-	}
-
-	/** Builder for a {@link Config}. */
-	public static class ConfigBuilder {
-		private boolean convertTableAccess = true;
-		private boolean decorrelationEnabled = true;
-		private boolean trimUnusedFields = false;
-		private boolean createValuesRel = true;
-		private boolean explain;
-		private boolean expand = true;
-		private int inSubQueryThreshold = DEFAULT_IN_SUB_QUERY_THRESHOLD;
-		private RelBuilderFactory relBuilderFactory = RelFactories.LOGICAL_BUILDER;
-
-		private ConfigBuilder() {}
-
-		/** Sets configuration identical to a given {@link Config}. */
-		public ConfigBuilder withConfig(Config config) {
-			this.convertTableAccess = config.isConvertTableAccess();
-			this.decorrelationEnabled = config.isDecorrelationEnabled();
-			this.trimUnusedFields = config.isTrimUnusedFields();
-			this.createValuesRel = config.isCreateValuesRel();
-			this.explain = config.isExplain();
-			this.expand = config.isExpand();
-			this.inSubQueryThreshold = config.getInSubQueryThreshold();
-			this.relBuilderFactory = config.getRelBuilderFactory();
-			return this;
-		}
-
-		public ConfigBuilder withConvertTableAccess(boolean convertTableAccess) {
-			this.convertTableAccess = convertTableAccess;
-			return this;
-		}
-
-		public ConfigBuilder withDecorrelationEnabled(boolean enabled) {
-			this.decorrelationEnabled = enabled;
-			return this;
-		}
-
-		public ConfigBuilder withTrimUnusedFields(boolean trimUnusedFields) {
-			this.trimUnusedFields = trimUnusedFields;
-			return this;
-		}
-
-		public ConfigBuilder withCreateValuesRel(boolean createValuesRel) {
-			this.createValuesRel = createValuesRel;
-			return this;
-		}
-
-		public ConfigBuilder withExplain(boolean explain) {
-			this.explain = explain;
-			return this;
-		}
-
-		public ConfigBuilder withExpand(boolean expand) {
-			this.expand = expand;
-			return this;
-		}
-
-		@Deprecated // to be removed before 2.0
-		public ConfigBuilder withInSubqueryThreshold(int inSubQueryThreshold) {
-			return withInSubQueryThreshold(inSubQueryThreshold);
-		}
-
-		public ConfigBuilder withInSubQueryThreshold(int inSubQueryThreshold) {
-			this.inSubQueryThreshold = inSubQueryThreshold;
-			return this;
-		}
-
-		public ConfigBuilder withRelBuilderFactory(
-				RelBuilderFactory relBuilderFactory) {
-			this.relBuilderFactory = relBuilderFactory;
-			return this;
-		}
-
-		/** Builds a {@link Config}. */
-		public Config build() {
-			return new ConfigImpl(convertTableAccess, decorrelationEnabled,
-					trimUnusedFields, createValuesRel, explain, expand,
-					inSubQueryThreshold, relBuilderFactory);
-		}
-	}
-
-	/** Implementation of {@link Config}.
-	 * Called by builder; all values are in private final fields. */
-	private static class ConfigImpl implements Config {
-		private final boolean convertTableAccess;
-		private final boolean decorrelationEnabled;
-		private final boolean trimUnusedFields;
-		private final boolean createValuesRel;
-		private final boolean explain;
-		private final boolean expand;
-		private final int inSubQueryThreshold;
-		private final RelBuilderFactory relBuilderFactory;
-
-		private ConfigImpl(boolean convertTableAccess, boolean decorrelationEnabled,
-		                   boolean trimUnusedFields, boolean createValuesRel, boolean explain,
-		                   boolean expand, int inSubQueryThreshold,
-		                   RelBuilderFactory relBuilderFactory) {
-			this.convertTableAccess = convertTableAccess;
-			this.decorrelationEnabled = decorrelationEnabled;
-			this.trimUnusedFields = trimUnusedFields;
-			this.createValuesRel = createValuesRel;
-			this.explain = explain;
-			this.expand = expand;
-			this.inSubQueryThreshold = inSubQueryThreshold;
-			this.relBuilderFactory = relBuilderFactory;
-		}
-
-		public boolean isConvertTableAccess() {
-			return convertTableAccess;
-		}
-
-		public boolean isDecorrelationEnabled() {
-			return decorrelationEnabled;
-		}
-
-		public boolean isTrimUnusedFields() {
-			return trimUnusedFields;
-		}
-
-		public boolean isCreateValuesRel() {
-			return createValuesRel;
-		}
-
-		public boolean isExplain() {
-			return explain;
-		}
-
-		public boolean isExpand() {
-			return expand;
-		}
-
-		public int getInSubQueryThreshold() {
-			return inSubQueryThreshold;
-		}
-
-		public RelBuilderFactory getRelBuilderFactory() {
-			return relBuilderFactory;
-		}
-	}
-}
-
-// End SqlToRelConverter.java
diff --git a/flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/rules/logical/LogicalUnnestRule.scala b/flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/rules/logical/LogicalUnnestRule.scala
index 8ef9fd3..f985a80 100644
--- a/flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/rules/logical/LogicalUnnestRule.scala
+++ b/flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/rules/logical/LogicalUnnestRule.scala
@@ -50,8 +50,16 @@ class LogicalUnnestRule(
       case filter: LogicalFilter =>
         filter.getInput.asInstanceOf[RelSubset].getOriginal match {
           case u: Uncollect => !u.withOrdinality
+          case p: LogicalProject => p.getInput.asInstanceOf[RelSubset].getOriginal match {
+            case u: Uncollect => !u.withOrdinality
+            case _ => false
+          }
           case _ => false
         }
+      case p: LogicalProject => p.getInput.asInstanceOf[RelSubset].getOriginal match {
+        case u: Uncollect => !u.withOrdinality
+        case _ => false
+      }
       case u: Uncollect => !u.withOrdinality
       case _ => false
     }
@@ -68,6 +76,11 @@ class LogicalUnnestRule(
         case rs: RelSubset =>
           convert(rs.getRelList.get(0))
 
+        case p: LogicalProject =>
+          p.copy(
+            p.getTraitSet,
+            ImmutableList.of(convert(p.getInput.asInstanceOf[RelSubset].getOriginal)))
+
         case f: LogicalFilter =>
           f.copy(
             f.getTraitSet,