jihoonson commented on a change in pull request #8487: Add initial SQL support for non-expression sketch postaggs URL: https://github.com/apache/incubator-druid/pull/8487#discussion_r327947754
########## File path: extensions-core/datasketches/src/main/java/org/apache/druid/query/aggregation/datasketches/hll/sql/HllSketchApproxCountDistinctSqlAggregator.java ########## @@ -0,0 +1,211 @@ +/* + * 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.druid.query.aggregation.datasketches.hll.sql; + +import org.apache.calcite.rel.core.AggregateCall; +import org.apache.calcite.rel.core.Project; +import org.apache.calcite.rex.RexBuilder; +import org.apache.calcite.rex.RexLiteral; +import org.apache.calcite.rex.RexNode; +import org.apache.calcite.sql.SqlAggFunction; +import org.apache.calcite.sql.SqlFunctionCategory; +import org.apache.calcite.sql.SqlKind; +import org.apache.calcite.sql.type.InferTypes; +import org.apache.calcite.sql.type.OperandTypes; +import org.apache.calcite.sql.type.ReturnTypes; +import org.apache.calcite.sql.type.SqlTypeFamily; +import org.apache.calcite.sql.type.SqlTypeName; +import org.apache.druid.java.util.common.ISE; +import org.apache.druid.query.aggregation.AggregatorFactory; +import org.apache.druid.query.aggregation.datasketches.hll.HllSketchAggregatorFactory; +import org.apache.druid.query.aggregation.datasketches.hll.HllSketchBuildAggregatorFactory; +import org.apache.druid.query.aggregation.datasketches.hll.HllSketchMergeAggregatorFactory; +import org.apache.druid.query.aggregation.post.FinalizingFieldAccessPostAggregator; +import org.apache.druid.query.dimension.DefaultDimensionSpec; +import org.apache.druid.query.dimension.DimensionSpec; +import org.apache.druid.segment.VirtualColumn; +import org.apache.druid.segment.column.ValueType; +import org.apache.druid.sql.calcite.aggregation.Aggregation; +import org.apache.druid.sql.calcite.aggregation.SqlAggregator; +import org.apache.druid.sql.calcite.expression.DruidExpression; +import org.apache.druid.sql.calcite.expression.Expressions; +import org.apache.druid.sql.calcite.planner.Calcites; +import org.apache.druid.sql.calcite.planner.PlannerContext; +import org.apache.druid.sql.calcite.rel.VirtualColumnRegistry; +import org.apache.druid.sql.calcite.table.RowSignature; + +import javax.annotation.Nullable; +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; + +public class HllSketchApproxCountDistinctSqlAggregator implements SqlAggregator +{ + private static final SqlAggFunction FUNCTION_INSTANCE = new HllSketchApproxCountDistinctSqlAggFunction(); + private static final String NAME = "APPROX_COUNT_DISTINCT_DS_HLL"; + private static final boolean ROUND = true; + + @Override + public SqlAggFunction calciteFunction() + { + return FUNCTION_INSTANCE; + } + + @Nullable + @Override + public Aggregation toDruidAggregation( + PlannerContext plannerContext, + RowSignature rowSignature, + VirtualColumnRegistry virtualColumnRegistry, + RexBuilder rexBuilder, + String name, + AggregateCall aggregateCall, + Project project, + List<Aggregation> existingAggregations, + boolean finalizeAggregations + ) + { + // Don't use Aggregations.getArgumentsForSimpleAggregator, since it won't let us use direct column access Review comment: Looks like most of this method is duplicate with `HllSketchSqlAggregator.toDruidAggregation()`. Can we add a super class that has a method like ```createAggregation(List<VirtualColumn> virtualColumns, AggregatorFactory aggregatorFactory)```? The method `toDruidAggregation()` of the super class can compute this common part and call `createAggregation()` of its children. `HllSketchApproxCountDistinctSqlAggregator` and `HllSketchSqlAggregator` can inherit this class. ---------------------------------------------------------------- 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: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
