/**
* 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.mapr.db;
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 org.apache.drill.exec.store.hbase.HBaseScanSpec;
import org.apache.drill.exec.store.mapr.db.binary.BinaryTableGroupScan;
import org.apache.drill.exec.store.mapr.db.binary.MapRDBFilterBuilder;
import org.apache.drill.exec.store.mapr.db.json.JsonConditionBuilder;
import org.apache.drill.exec.store.mapr.db.json.JsonScanSpec;
import org.apache.drill.exec.store.mapr.db.json.JsonTableGroupScan;
import com.google.common.collect.ImmutableList;
public abstract class MapRDBPushFilterIntoScan extends StoragePluginOptimizerRule {
static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(MapRDBPushFilterIntoScan.class);
private MapRDBPushFilterIntoScan(RelOptRuleOperand operand, String description) {
super(operand, description);
}
public static final StoragePluginOptimizerRule FILTER_ON_SCAN = new MapRDBPushFilterIntoScan(RelOptHelper.some(FilterPrel.class, RelOptHelper.any(ScanPrel.class)), "MapRDBPushFilterIntoScan: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();
if (scan.getGroupScan() instanceof BinaryTableGroupScan) {
BinaryTableGroupScan groupScan = (BinaryTableGroupScan)scan.getGroupScan();
doPushFilterIntoBinaryGroupScan(call, filter, null, scan, groupScan, condition);
} else {
assert(scan.getGroupScan() instanceof JsonTableGroupScan);
JsonTableGroupScan groupScan = (JsonTableGroupScan)scan.getGroupScan();
doPushFilterIntoJsonGroupScan(call, filter, null, scan, groupScan, condition);
}
}
@Override
public boolean matches(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(1);
if (scan.getGroupScan() instanceof BinaryTableGroupScan ||
scan.getGroupScan() instanceof JsonTableGroupScan) {
return super.matches(call);
}
return false;
}
};
public static final StoragePluginOptimizerRule FILTER_ON_PROJECT = new MapRDBPushFilterIntoScan(RelOptHelper.some(FilterPrel.class, RelOptHelper.some(ProjectPrel.class, RelOptHelper.any(ScanPrel.class))), "MapRDBPushFilterIntoScan: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);
// convert the filter to one that references the child of the project
final RexNode condition = RelOptUtil.pushPastProject(filter.getCondition(), project);
if (scan.getGroupScan() instanceof BinaryTableGroupScan) {
BinaryTableGroupScan groupScan = (BinaryTableGroupScan)scan.getGroupScan();
doPushFilterIntoBinaryGroupScan(call, filter, project, scan, groupScan, condition);
} else {
assert(scan.getGroupScan() instanceof JsonTableGroupScan);
JsonTableGroupScan groupScan = (JsonTableGroupScan)scan.getGroupScan();
doPushFilterIntoJsonGroupScan(call, filter, project, scan, groupScan, condition);
}
}
@Override
public boolean matches(RelOptRuleCall call) {
final ScanPrel scan = (ScanPrel) call.rel(2);
if (scan.getGroupScan() instanceof BinaryTableGroupScan ||
scan.getGroupScan() instanceof JsonTableGroupScan) {
return super.matches(call);
}
return false;
}
};
protected void doPushFilterIntoJsonGroupScan(RelOptRuleCall call,
FilterPrel filter, final ProjectPrel project, ScanPrel scan,
JsonTableGroupScan groupScan, RexNode condition) {
if (groupScan.isDisablePushdown() // Do not pushdown filter if it is disabled in plugin configuration
|| groupScan.isFilterPushedDown()) { // see below
/*
* 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;
}
LogicalExpression conditionExp = null;
try {
conditionExp = DrillOptiq.toDrill(new DrillParseContext(PrelUtil.getPlannerSettings(call.getPlanner())), scan, condition);
} catch (ClassCastException e) {
// MD-771 bug in DrillOptiq.toDrill() causes filter condition on ITEM operator to throw ClassCastException
// For such cases, we return without pushdown
return;
}
final JsonConditionBuilder jsonConditionBuilder = new JsonConditionBuilder(groupScan, conditionExp);
final JsonScanSpec newScanSpec = jsonConditionBuilder.parseTree();
if (newScanSpec == null) {
return; //no filter pushdown ==> No transformation.
}
// clone the groupScan with the newScanSpec.
final JsonTableGroupScan newGroupsScan = groupScan.clone(newScanSpec);
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 (jsonConditionBuilder.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)));
}
}
protected void doPushFilterIntoBinaryGroupScan(final RelOptRuleCall call,
final FilterPrel filter,
final ProjectPrel project,
final ScanPrel scan,
final BinaryTableGroupScan groupScan,
final RexNode condition) {
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;
}
final LogicalExpression conditionExp = DrillOptiq.toDrill(new DrillParseContext(PrelUtil.getPlannerSettings(call.getPlanner())), scan, condition);
final MapRDBFilterBuilder maprdbFilterBuilder = new MapRDBFilterBuilder(groupScan, conditionExp);
final HBaseScanSpec newScanSpec = maprdbFilterBuilder.parseTree();
if (newScanSpec == null) {
return; //no filter pushdown ==> No transformation.
}
// Pass tableStats from old groupScan so we do not go and fetch stats (an expensive operation) again from MapR DB client.
final BinaryTableGroupScan newGroupsScan = new BinaryTableGroupScan(groupScan.getUserName(), groupScan.getStoragePlugin(),
groupScan.getFormatPlugin(), newScanSpec, groupScan.getColumns(),
groupScan.getTableStats());
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 (maprdbFilterBuilder.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)));
}
}
}