akkapur commented on a change in pull request #1888: URL: https://github.com/apache/drill/pull/1888#discussion_r426306942
########## File path: contrib/storage-druid/src/main/java/org/apache/drill/exec/store/druid/DruidPushDownFilterForScan.java ########## @@ -0,0 +1,108 @@ +/* + * 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.drill.exec.store.druid; + +import com.fasterxml.jackson.core.JsonProcessingException; +import org.apache.calcite.plan.RelOptRuleCall; +import org.apache.calcite.rel.RelNode; +import org.apache.calcite.rex.RexNode; +import org.apache.drill.common.expression.LogicalExpression; +import org.apache.drill.exec.planner.logical.DrillOptiq; +import org.apache.drill.exec.planner.logical.DrillParseContext; +import org.apache.drill.exec.planner.logical.RelOptHelper; +import org.apache.drill.exec.planner.physical.FilterPrel; +import org.apache.drill.exec.planner.physical.PrelUtil; +import org.apache.drill.exec.planner.physical.ScanPrel; +import org.apache.drill.exec.store.StoragePluginOptimizerRule; +import org.apache.drill.shaded.guava.com.google.common.collect.ImmutableList; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class DruidPushDownFilterForScan extends StoragePluginOptimizerRule { + + private static final Logger logger = LoggerFactory.getLogger(DruidPushDownFilterForScan.class); + + public static final StoragePluginOptimizerRule INSTANCE = new DruidPushDownFilterForScan(); + + private DruidPushDownFilterForScan() { + super( + RelOptHelper.some(FilterPrel.class, RelOptHelper.any(ScanPrel.class)), + "DruidPushDownFilterForScan"); + } + + @Override + public void onMatch(RelOptRuleCall relOptRuleCall) { + final ScanPrel scan = (ScanPrel) relOptRuleCall.rel(1); + final FilterPrel filter = (FilterPrel) relOptRuleCall.rel(0); + final RexNode condition = filter.getCondition(); + + DruidGroupScan groupScan = (DruidGroupScan) scan.getGroupScan(); + if (groupScan.isFilterPushedDown()) { + return; + } + + LogicalExpression conditionExp = + DrillOptiq.toDrill( + new DrillParseContext(PrelUtil.getPlannerSettings(relOptRuleCall.getPlanner())), + scan, + condition); + + DruidFilterBuilder druidFilterBuilder = + new DruidFilterBuilder(groupScan, conditionExp); + + DruidScanSpec newScanSpec = null; + try { + newScanSpec = druidFilterBuilder.parseTree(); + } catch (JsonProcessingException e) { + logger.error("Error in onMatch. Exception - " + e.getMessage()); + } + if (newScanSpec == null) { + return; // no filter pushdown so nothing to apply. + } + + DruidGroupScan newGroupsScan = + new DruidGroupScan( + groupScan.getUserName(), + groupScan.getStoragePlugin(), + newScanSpec, + groupScan.getColumns()); + newGroupsScan.setFilterPushedDown(true); + + final ScanPrel newScanPrel = ScanPrel.create(scan, filter.getTraitSet(), + newGroupsScan, scan.getRowType()); + if (druidFilterBuilder.isAllExpressionsConverted()) { + /* + * Since we could convert the entire filter condition expression into an + * Druid filter, we can eliminate the filter operator altogether. + */ + relOptRuleCall.transformTo(newScanPrel); + } else { + relOptRuleCall.transformTo(filter.copy(filter.getTraitSet(), + ImmutableList.of((RelNode) newScanPrel))); + } + } + + @Override + public boolean matches(RelOptRuleCall call) { + final ScanPrel scan = (ScanPrel) call.rel(1); Review comment: Fixed. ---------------------------------------------------------------- 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: us...@infra.apache.org
