[GitHub] [calcite] hsyuan commented on a change in pull request #1953: [CALCITE-3896] Top down trait request

[GitBox <gi...@apache.org>]

hsyuan commented on a change in pull request #1953:
URL: https://github.com/apache/calcite/pull/1953#discussion_r421750834



##########
File path: core/src/main/java/org/apache/calcite/adapter/enumerable/EnumerableSortedAggregate.java
##########
@@ -0,0 +1,98 @@
+/*
+ * 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.adapter.enumerable;
+
+import org.apache.calcite.plan.RelOptCluster;
+import org.apache.calcite.plan.RelTraitSet;
+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.core.Aggregate;
+import org.apache.calcite.rel.core.AggregateCall;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.util.ImmutableBitSet;
+import org.apache.calcite.util.Pair;
+import org.apache.calcite.util.Util;
+import org.apache.calcite.util.mapping.Mappings;
+
+import com.google.common.collect.ImmutableList;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Sort based physical implementation of {@link Aggregate} in
+ * {@link EnumerableConvention enumerable calling convention}. */
+public class EnumerableSortedAggregate extends Aggregate implements EnumerableRel {
+  public EnumerableSortedAggregate(
+      RelOptCluster cluster,
+      RelTraitSet traitSet,
+      RelNode input,
+      ImmutableBitSet groupSet,
+      List<ImmutableBitSet> groupSets,
+      List<AggregateCall> aggCalls) {
+    super(cluster, traitSet, ImmutableList.of(), input, groupSet, groupSets, aggCalls);
+    assert getConvention() instanceof EnumerableConvention;
+  }
+
+  @Override public EnumerableSortedAggregate copy(RelTraitSet traitSet, RelNode input,
+      ImmutableBitSet groupSet,
+      List<ImmutableBitSet> groupSets, List<AggregateCall> aggCalls) {
+    return new EnumerableSortedAggregate(getCluster(), traitSet, input,
+        groupSet, groupSets, aggCalls);
+  }
+
+  @Override public Pair<RelTraitSet, List<RelTraitSet>> passThroughTraits(
+      final RelTraitSet required) {
+    if (!isSimple(this)) {
+      return null;
+    }
+
+    RelTraitSet inputTraits = getInput().getTraitSet();
+    RelCollation collation = required.getTrait(RelCollationTraitDef.INSTANCE);
+    ImmutableBitSet requiredKeys = ImmutableBitSet.of(RelCollations.ordinals(collation));
+    ImmutableBitSet groupKeys = ImmutableBitSet.range(groupSet.cardinality());
+
+    if (!groupKeys.contains(requiredKeys)) {
+      return null;
+    }
+
+    Mappings.TargetMapping mapping = Mappings.source(groupSet.toList(),
+        input.getRowType().getFieldCount());
+
+    if (requiredKeys.equals(groupKeys)) {
+      RelCollation inputCollation = RexUtil.apply(mapping, collation);
+      return Pair.of(required, ImmutableList.of(inputTraits.replace(inputCollation)));
+    } else if (groupKeys.contains(requiredKeys)) {
+      // group by a,b,c order by c,b
+      List<RelFieldCollation> list = new ArrayList<>(collation.getFieldCollations());
+      groupKeys.except(requiredKeys).forEach(k -> list.add(new RelFieldCollation(k)));
+      RelCollation aggCollation = RelCollations.of(list);
+      RelCollation inputCollation = RexUtil.apply(mapping, aggCollation);
+      return Pair.of(traitSet.replace(aggCollation),
+          ImmutableList.of(inputTraits.replace(inputCollation)));
+    }
+
+    // should not reach here
+    return null;
+  }

Review comment:
       done




----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org