com.hazelcast.org.apache.calcite.schema.impl.ModifiableViewTable Maven / Gradle / Ivy
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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.
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package com.hazelcast.org.apache.calcite.schema.impl;
import com.hazelcast.org.apache.calcite.plan.RelOptTable;
import com.hazelcast.org.apache.calcite.plan.RelOptUtil;
import com.hazelcast.org.apache.calcite.rel.type.RelDataType;
import com.hazelcast.org.apache.calcite.rel.type.RelDataTypeFactory;
import com.hazelcast.org.apache.calcite.rel.type.RelDataTypeField;
import com.hazelcast.org.apache.calcite.rel.type.RelDataTypeImpl;
import com.hazelcast.org.apache.calcite.rel.type.RelProtoDataType;
import com.hazelcast.org.apache.calcite.rex.RexBuilder;
import com.hazelcast.org.apache.calcite.rex.RexNode;
import com.hazelcast.org.apache.calcite.schema.ColumnStrategy;
import com.hazelcast.org.apache.calcite.schema.ExtensibleTable;
import com.hazelcast.org.apache.calcite.schema.ModifiableView;
import com.hazelcast.org.apache.calcite.schema.Path;
import com.hazelcast.org.apache.calcite.schema.Table;
import com.hazelcast.org.apache.calcite.schema.Wrapper;
import com.hazelcast.org.apache.calcite.sql.SqlFunction;
import com.hazelcast.org.apache.calcite.sql2rel.InitializerContext;
import com.hazelcast.org.apache.calcite.sql2rel.InitializerExpressionFactory;
import com.hazelcast.org.apache.calcite.sql2rel.NullInitializerExpressionFactory;
import com.hazelcast.org.apache.calcite.util.ImmutableIntList;
import com.hazelcast.com.google.common.collect.ImmutableList;
import com.hazelcast.com.google.common.collect.ImmutableMap;
import com.hazelcast.org.checkerframework.checker.nullness.qual.Nullable;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static com.hazelcast.org.apache.calcite.sql.validate.SqlValidatorUtil.mapNameToIndex;
import static java.util.Objects.requireNonNull;
/** Extension to {@link ViewTable} that is modifiable. */
public class ModifiableViewTable extends ViewTable
implements ModifiableView, Wrapper {
private final Table table;
private final Path tablePath;
private final RexNode constraint;
private final ImmutableIntList columnMapping;
private final InitializerExpressionFactory initializerExpressionFactory;
/** Creates a ModifiableViewTable. */
public ModifiableViewTable(Type elementType, RelProtoDataType rowType,
String viewSql, List schemaPath, @Nullable List viewPath,
Table table, Path tablePath, RexNode constraint,
ImmutableIntList columnMapping) {
super(elementType, rowType, viewSql, schemaPath, viewPath);
this.table = table;
this.tablePath = tablePath;
this.constraint = constraint;
this.columnMapping = columnMapping;
this.initializerExpressionFactory = new ModifiableViewTableInitializerExpressionFactory();
}
@Override public RexNode getConstraint(RexBuilder rexBuilder,
RelDataType tableRowType) {
return rexBuilder.copy(constraint);
}
@Override public ImmutableIntList getColumnMapping() {
return columnMapping;
}
@Override public Table getTable() {
return table;
}
@Override public Path getTablePath() {
return tablePath;
}
@Override public @Nullable C unwrap(Class aClass) {
if (aClass.isInstance(initializerExpressionFactory)) {
return aClass.cast(initializerExpressionFactory);
} else if (aClass.isInstance(table)) {
return aClass.cast(table);
}
return super.unwrap(aClass);
}
/**
* Extends the underlying table and returns a new view with updated row-type
* and column-mapping.
*
* The type factory is used to perform some scratch calculations, viz the
* type mapping, but the "real" row-type will be assigned later, when the
* table has been bound to the statement's type factory. The is important,
* because adding types to type factories that do not belong to a statement
* could potentially leak memory.
*
* @param extendedColumns Extended fields
* @param typeFactory Type factory
*/
public final ModifiableViewTable extend(
List extendedColumns, RelDataTypeFactory typeFactory) {
final ExtensibleTable underlying = unwrap(ExtensibleTable.class);
assert underlying != null;
final RelDataTypeFactory.Builder builder = typeFactory.builder();
final RelDataType rowType = getRowType(typeFactory);
for (RelDataTypeField column : rowType.getFieldList()) {
builder.add(column);
}
for (RelDataTypeField column : extendedColumns) {
builder.add(column);
}
// The characteristics of the new view.
final RelDataType newRowType = builder.build();
final ImmutableIntList newColumnMapping =
getNewColumnMapping(underlying, getColumnMapping(), extendedColumns,
typeFactory);
// Extend the underlying table with only the fields that
// duplicate column names in neither the view nor the base table.
final List underlyingColumns =
underlying.getRowType(typeFactory).getFieldList();
final List columnsOfExtendedBaseTable =
RelOptUtil.deduplicateColumns(underlyingColumns, extendedColumns);
final List extendColumnsOfBaseTable =
columnsOfExtendedBaseTable.subList(
underlyingColumns.size(), columnsOfExtendedBaseTable.size());
final Table extendedTable = underlying.extend(extendColumnsOfBaseTable);
return extend(extendedTable, RelDataTypeImpl.proto(newRowType),
newColumnMapping);
}
/**
* Creates a mapping from the view index to the index in the underlying table.
*/
private static ImmutableIntList getNewColumnMapping(Table underlying,
ImmutableIntList oldColumnMapping, List extendedColumns,
RelDataTypeFactory typeFactory) {
final List baseColumns =
underlying.getRowType(typeFactory).getFieldList();
final Map nameToIndex = mapNameToIndex(baseColumns);
final ImmutableList.Builder newMapping = ImmutableList.builder();
newMapping.addAll(oldColumnMapping);
int newMappedIndex = baseColumns.size();
for (RelDataTypeField extendedColumn : extendedColumns) {
String extendedColumnName = extendedColumn.getName();
if (nameToIndex.containsKey(extendedColumnName)) {
// The extended column duplicates a column in the underlying table.
// Map to the index in the underlying table.
newMapping.add(nameToIndex.get(extendedColumnName));
} else {
// The extended column is not in the underlying table.
newMapping.add(newMappedIndex++);
}
}
return ImmutableIntList.copyOf(newMapping.build());
}
protected ModifiableViewTable extend(Table extendedTable,
RelProtoDataType protoRowType, ImmutableIntList newColumnMapping) {
return new ModifiableViewTable(getElementType(), protoRowType, getViewSql(),
getSchemaPath(), getViewPath(), extendedTable, getTablePath(),
constraint, newColumnMapping);
}
/**
* Initializes columns based on the view constraint.
*/
private class ModifiableViewTableInitializerExpressionFactory
extends NullInitializerExpressionFactory {
private final ImmutableMap projectMap;
private ModifiableViewTableInitializerExpressionFactory() {
super();
final Map projectMap = new HashMap<>();
final List filters = new ArrayList<>();
RelOptUtil.inferViewPredicates(projectMap, filters, constraint);
assert filters.isEmpty();
this.projectMap = ImmutableMap.copyOf(projectMap);
}
@Override public ColumnStrategy generationStrategy(RelOptTable table,
int iColumn) {
final ModifiableViewTable viewTable = requireNonNull(
table.unwrap(ModifiableViewTable.class),
() -> "unable to unwrap ModifiableViewTable from " + table);
assert iColumn < viewTable.columnMapping.size();
// Use the view constraint to generate the default value if the column is
// constrained.
final int mappedOrdinal = viewTable.columnMapping.get(iColumn);
final RexNode viewConstraint = projectMap.get(mappedOrdinal);
if (viewConstraint != null) {
return ColumnStrategy.DEFAULT;
}
// Otherwise use the default value of the underlying table.
final Table schemaTable = viewTable.getTable();
if (schemaTable instanceof Wrapper) {
final InitializerExpressionFactory initializerExpressionFactory =
((Wrapper) schemaTable).unwrap(InitializerExpressionFactory.class);
if (initializerExpressionFactory != null) {
return initializerExpressionFactory.generationStrategy(table,
iColumn);
}
}
return super.generationStrategy(table, iColumn);
}
@Override public RexNode newColumnDefaultValue(RelOptTable table,
int iColumn, InitializerContext context) {
final ModifiableViewTable viewTable = requireNonNull(
table.unwrap(ModifiableViewTable.class),
() -> "unable to unwrap ModifiableViewTable from " + table);
assert iColumn < viewTable.columnMapping.size();
final RexBuilder rexBuilder = context.getRexBuilder();
final RelDataTypeFactory typeFactory = rexBuilder.getTypeFactory();
final RelDataType viewType = viewTable.getRowType(typeFactory);
final RelDataType iType = viewType.getFieldList().get(iColumn).getType();
// Use the view constraint to generate the default value if the column is constrained.
final int mappedOrdinal = viewTable.columnMapping.get(iColumn);
final RexNode viewConstraint = projectMap.get(mappedOrdinal);
if (viewConstraint != null) {
return rexBuilder.ensureType(iType, viewConstraint, true);
}
// Otherwise use the default value of the underlying table.
final Table schemaTable = viewTable.getTable();
if (schemaTable instanceof Wrapper) {
final InitializerExpressionFactory initializerExpressionFactory =
((Wrapper) schemaTable).unwrap(InitializerExpressionFactory.class);
if (initializerExpressionFactory != null) {
final RexNode tableConstraint =
initializerExpressionFactory.newColumnDefaultValue(table, iColumn,
context);
return rexBuilder.ensureType(iType, tableConstraint, true);
}
}
// Otherwise Sql type of NULL.
return super.newColumnDefaultValue(table, iColumn, context);
}
@Override public RexNode newAttributeInitializer(RelDataType type,
SqlFunction constructor, int iAttribute, List constructorArgs,
InitializerContext context) {
throw new UnsupportedOperationException("Not implemented - unknown requirements");
}
}
}