| /* |
| * 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.rel.core; |
| |
| import org.apache.calcite.linq4j.Ord; |
| import org.apache.calcite.plan.RelOptCluster; |
| import org.apache.calcite.plan.RelOptUtil; |
| import org.apache.calcite.plan.RelTraitSet; |
| import org.apache.calcite.rel.AbstractRelNode; |
| import org.apache.calcite.rel.RelInput; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.rel.RelWriter; |
| import org.apache.calcite.rel.hint.Hintable; |
| import org.apache.calcite.rel.hint.RelHint; |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.calcite.sql.SqlKind; |
| import org.apache.calcite.util.Util; |
| |
| import com.google.common.collect.ImmutableList; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| |
| /** |
| * <code>SetOp</code> is an abstract base for relational set operators such |
| * as UNION, MINUS (aka EXCEPT), and INTERSECT. |
| */ |
| public abstract class SetOp extends AbstractRelNode implements Hintable { |
| //~ Instance fields -------------------------------------------------------- |
| |
| protected ImmutableList<RelNode> inputs; |
| public final SqlKind kind; |
| public final boolean all; |
| protected final ImmutableList<RelHint> hints; |
| |
| //~ Constructors ----------------------------------------------------------- |
| |
| /** |
| * Creates a SetOp. |
| */ |
| protected SetOp(RelOptCluster cluster, RelTraitSet traits, List<RelHint> hints, |
| List<RelNode> inputs, SqlKind kind, boolean all) { |
| super(cluster, traits); |
| checkArgument(kind == SqlKind.UNION |
| || kind == SqlKind.INTERSECT |
| || kind == SqlKind.EXCEPT); |
| this.kind = kind; |
| this.inputs = ImmutableList.copyOf(inputs); |
| this.all = all; |
| this.hints = ImmutableList.copyOf(hints); |
| } |
| |
| /** |
| * Creates a SetOp. |
| */ |
| protected SetOp(RelOptCluster cluster, RelTraitSet traits, |
| List<RelNode> inputs, SqlKind kind, boolean all) { |
| this(cluster, traits, Collections.emptyList(), inputs, kind, all); |
| } |
| |
| /** |
| * Creates a SetOp by parsing serialized output. |
| */ |
| protected SetOp(RelInput input) { |
| this(input.getCluster(), input.getTraitSet(), Collections.emptyList(), |
| input.getInputs(), SqlKind.UNION, input.getBoolean("all", false)); |
| } |
| |
| //~ Methods ---------------------------------------------------------------- |
| |
| public abstract SetOp copy( |
| RelTraitSet traitSet, |
| List<RelNode> inputs, |
| boolean all); |
| |
| @Override public SetOp copy(RelTraitSet traitSet, List<RelNode> inputs) { |
| return copy(traitSet, inputs, all); |
| } |
| |
| @Override public void replaceInput(int ordinalInParent, RelNode p) { |
| final List<RelNode> newInputs = new ArrayList<>(inputs); |
| newInputs.set(ordinalInParent, p); |
| inputs = ImmutableList.copyOf(newInputs); |
| recomputeDigest(); |
| } |
| |
| @Override public List<RelNode> getInputs() { |
| return inputs; |
| } |
| |
| @Override public RelWriter explainTerms(RelWriter pw) { |
| super.explainTerms(pw); |
| for (Ord<RelNode> ord : Ord.zip(inputs)) { |
| pw.input("input#" + ord.i, ord.e); |
| } |
| return pw.item("all", all); |
| } |
| |
| @Override protected RelDataType deriveRowType() { |
| final List<RelDataType> inputRowTypes = |
| Util.transform(inputs, RelNode::getRowType); |
| final RelDataType rowType = |
| getCluster().getTypeFactory().leastRestrictive(inputRowTypes); |
| if (rowType == null) { |
| throw new IllegalArgumentException("Cannot compute compatible row type " |
| + "for arguments to set op: " |
| + Util.sepList(inputRowTypes, ", ")); |
| } |
| return rowType; |
| } |
| |
| @Override public ImmutableList<RelHint> getHints() { |
| return hints; |
| } |
| |
| /** |
| * Returns whether all the inputs of this set operator have the same row |
| * type as its output row. |
| * |
| * @param compareNames Whether column names are important in the |
| * homogeneity comparison |
| * @return Whether all the inputs of this set operator have the same row |
| * type as its output row |
| */ |
| public boolean isHomogeneous(boolean compareNames) { |
| RelDataType unionType = getRowType(); |
| for (RelNode input : getInputs()) { |
| if (!RelOptUtil.areRowTypesEqual( |
| input.getRowType(), unionType, compareNames)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| } |