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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to you under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.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.TableScan;
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.LogicalSnapshot;
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.SqlProperty;
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.SqlSnapshot;
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;
/**
* 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).
*
* 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 leaves = new ArrayList<>();
private final List 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 mapCorrelToDeferred =
new HashMap<>();
/**
* Stack of names of datasets requested by the
* TABLE(SAMPLE(<datasetName>, <query>)) construct.
*/
private final Deque 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 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 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 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 validatedFields =
validator.getValidatedNodeType(query).getFieldList();
final RelDataType validatedRowType =
validator.getTypeFactory().createStructType(
Pair.right(validatedFields),
SqlValidatorUtil.uniquify(Pair.left(validatedFields),
catalogReader.nameMatcher().isCaseSensitive()));
final List 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.
*
* 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}.
*
*
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 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;
* false 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; false 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 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 orderExprList = new ArrayList<>();
final List 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.
*
* 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 projectExprs = project.getProjects();
final List 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 squished = new HashMap<>();
final List fields = rel.getRowType().getFieldList();
final List> 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> 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 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 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 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 visitor =
new SqlBasicVisitor() {
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 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 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 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, > SOME, ...)
* @return converted expression
*/
private RexNode convertInToOr(
final Blackboard bb,
final List leftKeys,
SqlNodeList valuesList,
SqlInOperator op) {
final List 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 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> tupleList =
ImmutableList.builder();
final RelDataType rowType;
if (targetRowType != null) {
rowType = targetRowType;
} else {
rowType =
SqlTypeUtil.promoteToRowType(
typeFactory,
validator.getValidatedNodeType(rowList),
null);
}
final List unionInputs = new ArrayList<>();
for (SqlNode node : rows) {
SqlBasicCall call;
if (isRowConstructor(node)) {
call = (SqlBasicCall) node;
ImmutableList.Builder tuple = ImmutableList.builder();
for (Ord 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 IN or EXISTS 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 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 nameToNodeMap) {
final Map nameToTypeMap = new HashMap<>();
for (Map.Entry 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.
*
* 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 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 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:
*
*
* - a single table ("SALES.EMP"),
*
- an aliased table ("EMP AS E"),
*
- a list of tables ("EMP, DEPT"),
*
- an ANSI Join expression ("EMP JOIN DEPT ON EMP.DEPTNO =
* DEPT.DEPTNO"),
*
- a VALUES clause ("VALUES ('Fred', 20)"),
*
- a query ("(SELECT * FROM EMP WHERE GENDER = 'F')"),
*
- or any combination of the above.
*
*/
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 || bb.root instanceof Uncollect)) {
final List 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 SNAPSHOT:
snapshotTemporalTable(bb, (SqlCall) from);
return;
case CONFIGURABLE:
call = (SqlCall) from;
SqlIdentifier tableId = (SqlIdentifier) call.getOperandList().get(0);
SqlNodeList param = (SqlNodeList) call.getOperandList().get(1);
convertIdentifierWitTableHints(bb, tableId, param);
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 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 nodes = call.getOperandList();
final SqlUnnestOperator operator = (SqlUnnestOperator) call.getOperator();
for (SqlNode node : nodes) {
replaceSubQueries(bb, node, RelOptUtil.Logic.TRUE_FALSE_UNKNOWN);
}
final List exprs = new ArrayList<>();
final List fieldNames = new ArrayList<>();
for (Ord 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 partitionKeys = new ArrayList<>();
for (SqlNode partition : partitionList) {
RexNode e = matchBb.convertExpression(partition);
partitionKeys.add(e);
}
// ORDER BY
final SqlNodeList orderList = matchRecognize.getOrderList();
final List 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 patternVarsSet = new HashSet<>();
SqlNode pattern = matchRecognize.getPattern();
final SqlBasicVisitor patternVarVisitor =
new SqlBasicVisitor() {
@Override public RexNode visit(SqlCall call) {
List operands = call.getOperandList();
List 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> subsetMap = new HashMap<>();
for (SqlNode node : subsets) {
List operands = ((SqlCall) node).getOperandList();
SqlIdentifier left = (SqlIdentifier) operands.get(0);
patternVarsSet.add(left.getSimple());
SqlNodeList rights = (SqlNodeList) operands.get(1);
final TreeSet list = new TreeSet();
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 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 measureNodes =
ImmutableMap.builder();
for (SqlNode measure : matchRecognize.getMeasureList()) {
List 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 definitionNodes =
ImmutableMap.builder();
for (SqlNode def : matchRecognize.getPatternDefList()) {
replaceSubQueries(matchBb, def, RelOptUtil.Logic.UNKNOWN_AS_FALSE);
List operands = ((SqlCall) def).getOperandList();
String alias = ((SqlIdentifier) operands.get(1)).getSimple();
RexNode rex = matchBb.convertExpression(operands.get(0));
definitionNodes.put(alias, rex);
}
RexNode rowsPerMatchNode = null;
final SqlLiteral rowsPerMatch = matchRecognize.getRowsPerMatch();
if (rowsPerMatch != null) {
rowsPerMatchNode = matchBb.convertLiteral(rowsPerMatch);
}
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, rowsPerMatchNode, partitionKeys, orders, intervalNode);
bb.setRoot(rel, false);
}
private void convertIdentifierWitTableHints(Blackboard bb, SqlIdentifier id,
SqlNodeList param) {
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 (param != null && param.size() > 0) {
assert table != null;
Map paramMap = new HashMap<>();
for (SqlNode node : param.getList()) {
SqlProperty property = (SqlProperty) node;
paramMap.put(property.getKeyString(), property.getValueString());
}
table = table.config(paramMap);
}
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);
}
}
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 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 inputs = bb.retrieveCursors();
Set 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 void snapshotTemporalTable(Blackboard bb, SqlCall call) {
final SqlSnapshot snapshot = (SqlSnapshot) call;
RexNode rexCall = bb.convertExpression(snapshot.getPeriod());
// convert inner query, could be a table name or a derived table
SqlNode expr = snapshot.getTableRef();
convertFrom(bb, expr);
final TableScan scan = (TableScan) bb.root;
LogicalSnapshot snapshotRel = LogicalSnapshot.create(scan, rexCall);
bb.setRoot(snapshotRel, false);
}
private Set 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 correlatedVariables =
RelOptUtil.getVariablesUsed(r0);
if (correlatedVariables.isEmpty()) {
return null;
}
final ImmutableBitSet.Builder requiredColumns = ImmutableBitSet.builder();
final List 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 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 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 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 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 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 nameList) {
final SqlNameMatcher nameMatcher = catalogReader.nameMatcher();
final List list = new ArrayList<>();
for (String name : nameList) {
List 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.
*
* 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 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 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> 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> 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 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.
*
* In case the aggregate rel changes the order in which it projects
* fields, the groupExprProjection parameter is provided, and
* the implementation of this method may modify it.
*
*
The sortedCount 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 groupSets, List 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 extraOrderExprs 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 extraOrderExprs,
List 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 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}.
*
* The input relational expression is suitable for inserting into the view,
* and the returned relational expression is suitable for inserting into its
* delegate table.
*
*
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 projectMap = new HashMap<>();
final List 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> 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 schemaPath,
List 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 bb = () -> {
RexNode sourceRef = rexBuilder.makeRangeReference(scan);
return createInsertBlackboard(table, sourceRef,
table.getRowType().getFieldNames());
};
int virtualCount = 0;
final List 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.
*
* If the column list is not specified, source expressions match target
* columns in order.
*
*
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 targetColumnNames = new ArrayList<>();
final List columnExprs = new ArrayList<>();
collectInsertTargets(call, sourceRef, targetColumnNames, columnExprs);
final RelOptTable targetTable = getTargetTable(call);
final RelDataType targetRowType = RelOptTableImpl.realRowType(targetTable);
final List targetFields = targetRowType.getFieldList();
final List sourceExps =
new ArrayList<>(
Collections.nCopies(targetFields.size(), null));
final List 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 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 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 targetColumnNames) {
final Map nameToNodeMap = new HashMap<>();
int j = 0;
// Assign expressions for non-generated columns.
final List strategies = targetTable.getColumnStrategies();
final List 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 unwrap(Object o, Class 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 targetColumnNames,
List 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 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 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 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 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 level1InsertExprs = null;
List 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 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> 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 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 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