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Oct 13, 2025
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Merged

Improve performance of Merge for MarkDistinct #26759

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ba16252
Improve performance of Merge for MarkDistinct
hqbhoho Sep 30, 2025
c57f910
Add tests for Merge plan
hqbhoho Oct 11, 2025
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37 changes: 26 additions & 11 deletions core/trino-main/src/main/java/io/trino/sql/planner/QueryPlanner.java
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Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,6 @@
import io.trino.sql.ir.Expression;
import io.trino.sql.ir.FieldReference;
import io.trino.sql.ir.IsNull;
import io.trino.sql.ir.Logical;
import io.trino.sql.ir.Row;
import io.trino.sql.ir.WhenClause;
import io.trino.sql.planner.RelationPlanner.PatternRecognitionComponents;
Expand Down Expand Up @@ -751,9 +750,9 @@ public MergeWriterNode plan(Merge merge)
.process(merge.getTarget());

// Assign a unique id to every target table row
Symbol uniqueIdSymbol = symbolAllocator.newSymbol("unique_id", BIGINT);
Symbol targetUniqueIdSymbol = symbolAllocator.newSymbol("target_unique_id", BIGINT);
RelationPlan planWithUniqueId = new RelationPlan(
new AssignUniqueId(idAllocator.getNextId(), targetTablePlan.getRoot(), uniqueIdSymbol),
new AssignUniqueId(idAllocator.getNextId(), targetTablePlan.getRoot(), targetUniqueIdSymbol),
mergeAnalysis.getTargetTableScope(),
targetTablePlan.getFieldMappings(),
outerContext);
Expand All @@ -774,8 +773,16 @@ public MergeWriterNode plan(Merge merge)
RelationPlan source = new RelationPlanner(analysis, symbolAllocator, idAllocator, lambdaDeclarationToSymbolMap, plannerContext, outerContext, session, recursiveSubqueries)
.process(merge.getSource());

// Assign a unique id to every source table row
Symbol sourceUniqueIdSymbol = symbolAllocator.newSymbol("source_unique_id", BIGINT);
RelationPlan sourcePlanWithUniqueId = new RelationPlan(
new AssignUniqueId(idAllocator.getNextId(), source.getRoot(), sourceUniqueIdSymbol),
source.getScope(),
source.getFieldMappings(),
outerContext);

RelationPlan joinPlan = new RelationPlanner(analysis, symbolAllocator, idAllocator, lambdaDeclarationToSymbolMap, plannerContext, outerContext, session, recursiveSubqueries)
.planJoin(merge.getPredicate(), Join.Type.RIGHT, mergeAnalysis.getJoinScope(), planWithPresentColumn, source, analysis.getSubqueries(merge)); // TODO: ir
.planJoin(merge.getPredicate(), Join.Type.RIGHT, mergeAnalysis.getJoinScope(), planWithPresentColumn, sourcePlanWithUniqueId, analysis.getSubqueries(merge)); // TODO: ir

PlanBuilder subPlan = newPlanBuilder(joinPlan, analysis, lambdaDeclarationToSymbolMap, session, plannerContext);

Expand Down Expand Up @@ -864,10 +871,11 @@ public MergeWriterNode plan(Merge merge)

List<io.trino.sql.tree.Expression> constraints = analysis.getCheckConstraints(mergeAnalysis.getTargetTable());
if (!constraints.isEmpty()) {
assignments.putIdentity(uniqueIdSymbol);
assignments.putIdentity(targetUniqueIdSymbol);
assignments.putIdentity(sourceUniqueIdSymbol);
assignments.putIdentity(presentColumn);
assignments.putIdentity(rowIdSymbol);
assignments.putIdentities(source.getFieldMappings());
assignments.putIdentities(sourcePlanWithUniqueId.getFieldMappings());
subPlan = subPlan.withNewRoot(new ProjectNode(
idAllocator.getNextId(),
subPlan.getRoot(),
Expand Down Expand Up @@ -897,7 +905,15 @@ public MergeWriterNode plan(Merge merge)
Symbol symbol = planWithPresentColumn.getFieldMappings().get(fieldIndex);
projectionAssignmentsBuilder.putIdentity(symbol);
}
projectionAssignmentsBuilder.putIdentity(uniqueIdSymbol);

// Assigns a unique id to each joined row
// The target table unique_id for matches, and the source table unique_id for non-matches
// Avoid the scenario where unique_id values become null after right join due to unmatched rows.
// It can improve performance and parallelism when handling non-matches in a mark distinct operation.
Symbol uniqueIdSymbol = symbolAllocator.newSymbol("unique_id", BIGINT);
Expression uniqueIdExpression = new Coalesce(targetUniqueIdSymbol.toSymbolReference(), sourceUniqueIdSymbol.toSymbolReference());

projectionAssignmentsBuilder.put(uniqueIdSymbol, uniqueIdExpression);
projectionAssignmentsBuilder.putIdentity(rowIdSymbol);
projectionAssignmentsBuilder.put(mergeRowSymbol, caseExpression);

Expand All @@ -919,11 +935,10 @@ public MergeWriterNode plan(Merge merge)
Symbol isDistinctSymbol = symbolAllocator.newSymbol("is_distinct", BOOLEAN);
MarkDistinctNode markDistinctNode = new MarkDistinctNode(idAllocator.getNextId(), project, isDistinctSymbol, ImmutableList.of(uniqueIdSymbol, caseNumberSymbol));

// Raise an error if unique_id symbol is non-null and the unique_id/case_number combination was not distinct
// The unique_id which originates from either the source or target table will not be null
// Raise an error if the unique_id/case_number combination was not distinct
Expression filter = ifExpression(
Logical.and(
not(metadata, isDistinctSymbol.toSymbolReference()),
not(metadata, new IsNull(uniqueIdSymbol.toSymbolReference()))),
not(metadata, isDistinctSymbol.toSymbolReference()),
new Cast(
failFunction(metadata, MERGE_TARGET_ROW_MULTIPLE_MATCHES, "One MERGE target table row matched more than one source row"),
BOOLEAN),
Expand Down
155 changes: 155 additions & 0 deletions core/trino-main/src/test/java/io/trino/sql/planner/TestMerge.java
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Original file line number Diff line number Diff line change
@@ -0,0 +1,155 @@
/*
* Licensed 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 io.trino.sql.planner;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import io.trino.Session;
import io.trino.connector.MockConnectorColumnHandle;
import io.trino.connector.MockConnectorFactory;
import io.trino.connector.MockConnectorPlugin;
import io.trino.connector.MockConnectorTableHandle;
import io.trino.metadata.ResolvedFunction;
import io.trino.metadata.TestingFunctionResolution;
import io.trino.spi.connector.ColumnMetadata;
import io.trino.spi.predicate.TupleDomain;
import io.trino.spi.type.RowType;
import io.trino.spi.type.Type;
import io.trino.sql.ir.Call;
import io.trino.sql.ir.Case;
import io.trino.sql.ir.Cast;
import io.trino.sql.ir.Coalesce;
import io.trino.sql.ir.Constant;
import io.trino.sql.ir.FieldReference;
import io.trino.sql.ir.IsNull;
import io.trino.sql.ir.Reference;
import io.trino.sql.ir.Row;
import io.trino.sql.ir.WhenClause;
import io.trino.sql.planner.assertions.BasePlanTest;
import io.trino.testing.PlanTester;
import org.junit.jupiter.api.Test;

import static io.airlift.slice.Slices.utf8Slice;
import static io.trino.SystemSessionProperties.ENABLE_DYNAMIC_FILTERING;
import static io.trino.spi.StandardErrorCode.MERGE_TARGET_ROW_MULTIPLE_MATCHES;
import static io.trino.spi.type.BigintType.BIGINT;
import static io.trino.spi.type.BooleanType.BOOLEAN;
import static io.trino.spi.type.IntegerType.INTEGER;
import static io.trino.spi.type.TinyintType.TINYINT;
import static io.trino.spi.type.VarcharType.VARCHAR;
import static io.trino.sql.analyzer.TypeSignatureProvider.fromTypes;
import static io.trino.sql.ir.Booleans.TRUE;
import static io.trino.sql.planner.assertions.PlanMatchPattern.anyTree;
import static io.trino.sql.planner.assertions.PlanMatchPattern.assignUniqueId;
import static io.trino.sql.planner.assertions.PlanMatchPattern.expression;
import static io.trino.sql.planner.assertions.PlanMatchPattern.filter;
import static io.trino.sql.planner.assertions.PlanMatchPattern.join;
import static io.trino.sql.planner.assertions.PlanMatchPattern.markDistinct;
import static io.trino.sql.planner.assertions.PlanMatchPattern.project;
import static io.trino.sql.planner.assertions.PlanMatchPattern.tableScan;
import static io.trino.sql.planner.plan.JoinType.RIGHT;
import static io.trino.testing.TestingSession.testSessionBuilder;

public class TestMerge
extends BasePlanTest
{
private static final TestingFunctionResolution FUNCTIONS = new TestingFunctionResolution();
private static final ResolvedFunction FAIL = FUNCTIONS.resolveFunction("fail", fromTypes(INTEGER, VARCHAR));
private static final ResolvedFunction NOT = FUNCTIONS.resolveFunction("$not", fromTypes(BOOLEAN));
private static final Type ROW_TYPE = RowType.anonymousRow(INTEGER, INTEGER, BOOLEAN, TINYINT, INTEGER);

@Override
protected PlanTester createPlanTester()
{
Session.SessionBuilder sessionBuilder = testSessionBuilder()
.setCatalog("mock")
.setSchema("schema")
.setSystemProperty(ENABLE_DYNAMIC_FILTERING, "false");

PlanTester planTester = PlanTester.create(sessionBuilder.build());
planTester.installPlugin(
new MockConnectorPlugin(MockConnectorFactory.builder()
.withGetTableHandle((session, schemaTableName) -> {
if (schemaTableName.getTableName().equals("test_table_merge_target")) {
return new MockConnectorTableHandle(schemaTableName);
}

if (schemaTableName.getTableName().equals("test_table_merge_source")) {
return new MockConnectorTableHandle(schemaTableName);
}

return null;
})
.withGetColumns(name -> ImmutableList.of(
new ColumnMetadata("column1", INTEGER),
new ColumnMetadata("column2", INTEGER)))
.build()));
planTester.createCatalog("mock", "mock", ImmutableMap.of());
return planTester;
}

@Test
public void testMergeWithSimpleSelect()
{
// one join
assertPlan(
"MERGE INTO test_table_merge_target a " +
"USING test_table_merge_source b " +
"ON a.column1 = b.column1 " +
"WHEN MATCHED " +
"THEN UPDATE SET column2 = b.column2 " +
"WHEN NOT MATCHED " +
"THEN INSERT (column1 ,column2) VALUES (b.column1, b.column2)",
anyTree(
filter(
new Case(
ImmutableList.of(new WhenClause(new Call(NOT, ImmutableList.of(new Reference(BOOLEAN, "is_distinct"))), new Cast(new Call(FAIL, ImmutableList.of(new Constant(INTEGER, (long) MERGE_TARGET_ROW_MULTIPLE_MATCHES.toErrorCode().getCode()), new Constant(VARCHAR, utf8Slice("One MERGE target table row matched more than one source row")))), BOOLEAN))),
TRUE),
markDistinct("is_distinct", ImmutableList.of("unique_id", "case_number"),
anyTree(
project(ImmutableMap.of(
"unique_id", expression(new Coalesce(ImmutableList.of(new Reference(BIGINT, "target_unique_id"), new Reference(BIGINT, "source_unique_id")))),
"field", expression(new Reference(BIGINT, "field")),
"merge_row", expression(new Reference(ROW_TYPE, "merge_row")),
"case_number", expression(new FieldReference(new Reference(ROW_TYPE, "merge_row"), 4))),
project(ImmutableMap.of(
"field", expression(new Reference(BIGINT, "field")),
"merge_row", expression(new Case(
ImmutableList.of(
new WhenClause(new Reference(BOOLEAN, "present"), new Row(ImmutableList.of(new Reference(INTEGER, "column1"), new Reference(INTEGER, "column2_1"), new Call(NOT, ImmutableList.of(new IsNull(new Reference(BOOLEAN, "present")))), new Constant(TINYINT, 3L), new Constant(INTEGER, 0L)), ROW_TYPE)),
new WhenClause(new IsNull(new Reference(BOOLEAN, "present")), new Row(ImmutableList.of(new Reference(INTEGER, "column1_0"), new Reference(INTEGER, "column2_1"), new Call(NOT, ImmutableList.of(new IsNull(new Reference(BOOLEAN, "present")))), new Constant(TINYINT, 1L), new Constant(INTEGER, 1L)), ROW_TYPE))),
new Constant(ROW_TYPE, null))),
"target_unique_id", expression(new Reference(BIGINT, "target_unique_id")),
"source_unique_id", expression(new Reference(BIGINT, "source_unique_id"))),
join(RIGHT, builder -> builder
.equiCriteria("column1", "column1_0")
.left(
project(ImmutableMap.of(
"column1", expression(new Reference(INTEGER, "column1")),
"field", expression(new Reference(BIGINT, "field")),
"target_unique_id", expression(new Reference(BIGINT, "target_unique_id")),
"present", expression(new Constant(BOOLEAN, true))),
assignUniqueId("target_unique_id",
tableScan(
tableHandle -> ((MockConnectorTableHandle) tableHandle).getTableName().getTableName().equals("test_table_merge_target"),
TupleDomain.all(),
ImmutableMap.of(
"column1", columnHandle -> ((MockConnectorColumnHandle) columnHandle).name().equals("column1"),
"field", columnHandle -> ((MockConnectorColumnHandle) columnHandle).name().equals("merge_row_id"))))))
.right(
anyTree(
assignUniqueId("source_unique_id",
tableScan("test_table_merge_source", ImmutableMap.of("column1_0", "column1", "column2_1", "column2")))))))))))));
}
}