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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.
*/
package org.apache.drill.exec.store.hbase;
import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.calcite.plan.RelOptRuleOperand;
import org.apache.calcite.plan.RelOptUtil;
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.ProjectPrel;
import org.apache.drill.exec.planner.physical.ScanPrel;
import org.apache.drill.exec.store.StoragePluginOptimizerRule;
import com.google.common.collect.ImmutableList;
public abstract class HBasePushFilterIntoScan extends StoragePluginOptimizerRule {
private HBasePushFilterIntoScan(RelOptRuleOperand operand, String description) {
super(operand, description);
}
public static final StoragePluginOptimizerRule FILTER_ON_SCAN = new HBasePushFilterIntoScan(RelOptHelper.some(FilterPrel.class, RelOptHelper.any(ScanPrel.class)), "HBasePushFilterIntoScan:Filter_On_Scan") {
@Override
public void onMatch(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(1);
final FilterPrel filter = (FilterPrel) call.rel(0);
final RexNode condition = filter.getCondition();
HBaseGroupScan groupScan = (HBaseGroupScan)scan.getGroupScan();
if (groupScan.isFilterPushedDown()) {
/*
* The rule can get triggered again due to the transformed "scan => filter" sequence
* created by the earlier execution of this rule when we could not do a complete
* conversion of Optiq Filter's condition to HBase Filter. In such cases, we rely upon
* this flag to not do a re-processing of the rule on the already transformed call.
*/
return;
}
doPushFilterToScan(call, filter, null, scan, groupScan, condition);
}
@Override
public boolean matches(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(1);
if (scan.getGroupScan() instanceof HBaseGroupScan) {
return super.matches(call);
}
return false;
}
};
public static final StoragePluginOptimizerRule FILTER_ON_PROJECT = new HBasePushFilterIntoScan(RelOptHelper.some(FilterPrel.class, RelOptHelper.some(ProjectPrel.class, RelOptHelper.any(ScanPrel.class))), "HBasePushFilterIntoScan:Filter_On_Project") {
@Override
public void onMatch(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(2);
final ProjectPrel project = (ProjectPrel) call.rel(1);
final FilterPrel filter = (FilterPrel) call.rel(0);
HBaseGroupScan groupScan = (HBaseGroupScan)scan.getGroupScan();
if (groupScan.isFilterPushedDown()) {
/*
* The rule can get triggered again due to the transformed "scan => filter" sequence
* created by the earlier execution of this rule when we could not do a complete
* conversion of Optiq Filter's condition to HBase Filter. In such cases, we rely upon
* this flag to not do a re-processing of the rule on the already transformed call.
*/
return;
}
// convert the filter to one that references the child of the project
final RexNode condition = RelOptUtil.pushPastProject(filter.getCondition(), project);
doPushFilterToScan(call, filter, project, scan, groupScan, condition);
}
@Override
public boolean matches(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(2);
if (scan.getGroupScan() instanceof HBaseGroupScan) {
return super.matches(call);
}
return false;
}
};
protected void doPushFilterToScan(final RelOptRuleCall call, final FilterPrel filter, final ProjectPrel project, final ScanPrel scan, final HBaseGroupScan groupScan, final RexNode condition) {
final LogicalExpression conditionExp = DrillOptiq.toDrill(new DrillParseContext(PrelUtil.getPlannerSettings(call.getPlanner())), scan, condition);
final HBaseFilterBuilder hbaseFilterBuilder = new HBaseFilterBuilder(groupScan, conditionExp);
final HBaseScanSpec newScanSpec = hbaseFilterBuilder.parseTree();
if (newScanSpec == null) {
return; //no filter pushdown ==> No transformation.
}
final HBaseGroupScan newGroupsScan = new HBaseGroupScan(groupScan.getUserName(), groupScan.getStoragePlugin(),
newScanSpec, groupScan.getColumns());
newGroupsScan.setFilterPushedDown(true);
final ScanPrel newScanPrel = ScanPrel.create(scan, filter.getTraitSet(), newGroupsScan, scan.getRowType());
// Depending on whether is a project in the middle, assign either scan or copy of project to childRel.
final RelNode childRel = project == null ? newScanPrel : project.copy(project.getTraitSet(), ImmutableList.of((RelNode)newScanPrel));;
if (hbaseFilterBuilder.isAllExpressionsConverted()) {
/*
* Since we could convert the entire filter condition expression into an HBase filter,
* we can eliminate the filter operator altogether.
*/
call.transformTo(childRel);
} else {
call.transformTo(filter.copy(filter.getTraitSet(), ImmutableList.of(childRel)));
}
}
}