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Merged
feilong-liu merged 1 commit into from
Oct 22, 2024
+190 −29
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Extend join prefilter optimizer to use hash for filter #23858

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148 changes: 134 additions & 14 deletions presto-main/src/main/java/com/facebook/presto/sql/planner/optimizations/JoinPrefilter.java
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Original file line number Diff line number Diff line change
Expand Up @@ -14,6 +14,9 @@
package com.facebook.presto.sql.planner.optimizations;

import com.facebook.presto.Session;
import com.facebook.presto.common.function.OperatorType;
import com.facebook.presto.common.type.VarcharType;
import com.facebook.presto.metadata.FunctionAndTypeManager;
import com.facebook.presto.metadata.Metadata;
import com.facebook.presto.spi.VariableAllocator;
import com.facebook.presto.spi.WarningCollector;
Expand All @@ -22,6 +25,8 @@
import com.facebook.presto.spi.plan.FilterNode;
import com.facebook.presto.spi.plan.PlanNode;
import com.facebook.presto.spi.plan.PlanNodeIdAllocator;
import com.facebook.presto.spi.relation.CallExpression;
import com.facebook.presto.spi.relation.RowExpression;
import com.facebook.presto.spi.relation.VariableReferenceExpression;
import com.facebook.presto.sql.planner.TypeProvider;
import com.facebook.presto.sql.planner.plan.JoinNode;
Expand All @@ -34,18 +39,98 @@
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.stream.IntStream;

import static com.facebook.presto.SystemSessionProperties.isJoinPrefilterEnabled;
import static com.facebook.presto.common.type.BigintType.BIGINT;
import static com.facebook.presto.common.type.BooleanType.BOOLEAN;
import static com.facebook.presto.common.type.VarcharType.VARCHAR;
import static com.facebook.presto.spi.plan.AggregationNode.singleGroupingSet;
import static com.facebook.presto.spi.plan.JoinType.INNER;
import static com.facebook.presto.spi.plan.JoinType.LEFT;
import static com.facebook.presto.sql.planner.PlannerUtils.addProjections;
import static com.facebook.presto.sql.planner.PlannerUtils.clonePlanNode;
import static com.facebook.presto.sql.planner.PlannerUtils.isScanFilterProject;
import static com.facebook.presto.sql.planner.PlannerUtils.orNullHashCode;
import static com.facebook.presto.sql.planner.PlannerUtils.projectExpressions;
import static com.facebook.presto.sql.planner.PlannerUtils.restrictOutput;
import static com.facebook.presto.sql.planner.plan.ChildReplacer.replaceChildren;
import static com.facebook.presto.sql.relational.Expressions.call;
import static com.facebook.presto.sql.relational.Expressions.callOperator;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.collect.ImmutableList.toImmutableList;
import static java.util.Objects.requireNonNull;

/**
* This optimizer filter the right side of a join with the unique join keys on the left side of the join. When the join key is wide or
* there are multiple join keys, we are to do filter on the hash instead of using the keys.
* It will convert plan from
* <pre>
* - InnerJoin
* leftKey = rightKey
* - scan l
* - scan r
* </pre>
* into
* <pre>
* - InnerJoin
* leftKey = rightKey
* - scan l
* - semiJoin
* r.rightKey in l.leftKey
* - scan r
* - distinct aggregation
* group by leftKey
* - scan l
* </pre>
* And for join with varchar type
* <pre>
* - InnerJoin
* leftKey (varchar) = rightKey (varchar)
* - scan l
* - scan r
* </pre>
* into
* <pre>
* - InnerJoin
* leftKey (varchar) = rightKey (varchar)
* - scan l
* - semiJoin
* r.rightKeyHash in l.leftKeyHash
* - project
* r.rightKeyHash = xx_hash64(r.rightKey)
* - scan r
* - distinct aggregation
* group by leftKeyHash
* - project
* l.leftKeyHash = xx_hash64(l.leftKey)
* - scan l
* </pre>
* And for join with multiple keys
* <pre>
* - InnerJoin
* leftKey1 = rightKey1 and leftKey2 = rightKey2
* - scan l
* - scan r
* </pre>
* into
* <pre>
* - InnerJoin
* leftKey1 = rightKey1 and leftKey2 = rightKey2
* - scan l
* - semiJoin
* r.rightKeysHash in l.leftKeysHash
* - project
* r.rightKeysHash = combine_hash(xx_hash64(rightKey1), xx_hash64(rightKey2))
* - scan r
* - distinct aggregation
* group by leftKeysHash
* - project
* l.leftKeysHash = combine_hash(xx_hash64(leftKey1), xx_hash64(leftKey2))
* - scan l
* </pre>
*/

public class JoinPrefilter
implements PlanOptimizer
{
Expand Down Expand Up @@ -73,7 +158,7 @@ public boolean isEnabled(Session session)
public PlanOptimizerResult optimize(PlanNode plan, Session session, TypeProvider types, VariableAllocator variableAllocator, PlanNodeIdAllocator idAllocator, WarningCollector warningCollector)
{
if (isEnabled(session)) {
Rewriter rewriter = new Rewriter(session, metadata, idAllocator, variableAllocator);
Rewriter rewriter = new Rewriter(session, metadata, idAllocator, variableAllocator, metadata.getFunctionAndTypeManager());
PlanNode rewritten = SimplePlanRewriter.rewriteWith(rewriter, plan, null);
return PlanOptimizerResult.optimizerResult(rewritten, rewriter.isPlanChanged());
}
Expand All @@ -88,14 +173,16 @@ private static class Rewriter
private final Metadata metadata;
private final PlanNodeIdAllocator idAllocator;
private final VariableAllocator variableAllocator;
private final FunctionAndTypeManager functionAndTypeManager;
private boolean planChanged;

private Rewriter(Session session, Metadata metadata, PlanNodeIdAllocator idAllocator, VariableAllocator variableAllocator)
private Rewriter(Session session, Metadata metadata, PlanNodeIdAllocator idAllocator, VariableAllocator variableAllocator, FunctionAndTypeManager functionAndTypeManager)
{
this.session = requireNonNull(session, "session is null");
this.metadata = requireNonNull(metadata, "functionAndTypeManager is null");
this.idAllocator = requireNonNull(idAllocator, "idAllocator is null");
this.variableAllocator = requireNonNull(variableAllocator, "idAllocator is null");
this.functionAndTypeManager = requireNonNull(functionAndTypeManager, "functionAndTypeManager is null");
}

@Override
Expand All @@ -108,21 +195,37 @@ public PlanNode visitJoin(JoinNode node, RewriteContext<Void> context)
PlanNode rewrittenRight = rewriteWith(this, right);
List<EquiJoinClause> equiJoinClause = node.getCriteria();

// We apply this for only left and inner join and the left side of the join is a simple scan and the join is on one key
if (equiJoinClause.size() == 1 &&
(node.getType() == LEFT || node.getType() == INNER) &&
isScanFilterProject(rewrittenLeft)) {
VariableReferenceExpression leftKey = equiJoinClause.stream().map(x -> x.getLeft()).findFirst().get();
VariableReferenceExpression rightKey = equiJoinClause.stream().map(x -> x.getRight()).findFirst().get();
// We apply this for only left and inner join and the left side of the join is a simple scan
if ((node.getType() == LEFT || node.getType() == INNER) && isScanFilterProject(rewrittenLeft) && !node.getCriteria().isEmpty()) {
List<VariableReferenceExpression> leftKeyList = equiJoinClause.stream().map(EquiJoinClause::getLeft).collect(toImmutableList());
List<VariableReferenceExpression> rightKeyList = equiJoinClause.stream().map(EquiJoinClause::getRight).collect(toImmutableList());
checkState(IntStream.range(0, leftKeyList.size()).boxed().allMatch(i -> leftKeyList.get(i).getType().equals(rightKeyList.get(i).getType())));

boolean hashJoinKey = leftKeyList.size() > 1 || (leftKeyList.get(0).getType().equals(VARCHAR) || leftKeyList.get(0).getType() instanceof VarcharType);

// First create a SELECT DISTINCT leftKey FROM left
Map<VariableReferenceExpression, VariableReferenceExpression> leftVarMap = new HashMap();
PlanNode leftKeys = clonePlanNode(rewrittenLeft, session, metadata, idAllocator, ImmutableList.of(leftKey), leftVarMap);
PlanNode projectNode = projectExpressions(leftKeys, idAllocator, variableAllocator, ImmutableList.of(leftVarMap.get(leftKey)), ImmutableList.of());
PlanNode leftKeys = clonePlanNode(rewrittenLeft, session, metadata, idAllocator, leftKeyList, leftVarMap);
ImmutableList.Builder<RowExpression> expressionsToProject = ImmutableList.builder();
if (hashJoinKey) {
RowExpression hashExpression = getVariableHash(leftKeyList);
expressionsToProject.add(hashExpression);
}
else {
expressionsToProject.add(leftVarMap.get(leftKeyList.get(0)));
}
PlanNode projectNode = projectExpressions(leftKeys, idAllocator, variableAllocator, expressionsToProject.build(), ImmutableList.of());

VariableReferenceExpression rightKeyToFilter = rightKeyList.get(0);
if (hashJoinKey) {
RowExpression hashExpression = getVariableHash(rightKeyList);
rightKeyToFilter = variableAllocator.newVariable(hashExpression);
rewrittenRight = addProjections(rewrittenRight, idAllocator, ImmutableMap.of(rightKeyToFilter, hashExpression));
}

// DISTINCT on the leftkey
// DISTINCT on the leftkey or hash if wide column
PlanNode filteringSource = new AggregationNode(
leftKey.getSourceLocation(),
node.getLeft().getSourceLocation(),
idAllocator.getNextId(),
projectNode,
ImmutableMap.of(),
Expand All @@ -139,12 +242,12 @@ public PlanNode visitJoin(JoinNode node, RewriteContext<Void> context)
// Now we add a semijoin as the right side
VariableReferenceExpression semiJoinOutput = variableAllocator.newVariable("semiJoinOutput", BOOLEAN);
SemiJoinNode semiJoinNode = new SemiJoinNode(
rightKey.getSourceLocation(),
node.getRight().getSourceLocation(),
idAllocator.getNextId(),
node.getStatsEquivalentPlanNode(),
rewrittenRight,
filteringSource,
rightKey,
rightKeyToFilter,
filteringSource.getOutputVariables().get(0),
semiJoinOutput,
Optional.empty(),
Expand All @@ -153,6 +256,9 @@ public PlanNode visitJoin(JoinNode node, RewriteContext<Void> context)
ImmutableMap.of());

rewrittenRight = new FilterNode(semiJoinNode.getSourceLocation(), idAllocator.getNextId(), semiJoinNode, semiJoinOutput);
if (rewrittenRight.getOutputVariables().size() > node.getRight().getOutputVariables().size()) {
rewrittenRight = restrictOutput(rewrittenRight, idAllocator, node.getRight().getOutputVariables());
}
}

if (rewrittenLeft != node.getLeft() || rewrittenRight != node.getRight()) {
Expand All @@ -167,5 +273,19 @@ public boolean isPlanChanged()
{
return planChanged;
}

private RowExpression getVariableHash(List<VariableReferenceExpression> inputVariables)
{
List<CallExpression> hashExpressionList = inputVariables.stream().map(keyVariable ->
callOperator(functionAndTypeManager.getFunctionAndTypeResolver(), OperatorType.XX_HASH_64, BIGINT, keyVariable)).collect(toImmutableList());
RowExpression hashExpression = hashExpressionList.get(0);
if (hashExpressionList.size() > 1) {
hashExpression = orNullHashCode(hashExpression);
for (int i = 1; i < hashExpressionList.size(); ++i) {
hashExpression = call(functionAndTypeManager, "combine_hash", BIGINT, hashExpression, orNullHashCode(hashExpressionList.get(i)));
}
}
return hashExpression;
}
}
}
71 changes: 56 additions & 15 deletions presto-tests/src/main/java/com/facebook/presto/tests/AbstractTestQueries.java
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Original file line number Diff line number Diff line change
Expand Up @@ -7768,21 +7768,62 @@ public void testLambdaInAggregation()
@Test
public void testJoinPrefilter()
{
// Orig
String testQuery = "SELECT 1 from region join nation using(regionkey)";
MaterializedResult result = computeActual("explain(type distributed) " + testQuery);
assertEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(testQuery);
assertEquals(result.getRowCount(), 25);

// With feature
Session session = Session.builder(getSession())
.setSystemProperty(JOIN_PREFILTER_BUILD_SIDE, String.valueOf(true))
.build();
result = computeActual(session, "explain(type distributed) " + testQuery);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(session, testQuery);
assertEquals(result.getRowCount(), 25);
{
// Orig
String testQuery = "SELECT 1 from region join nation using(regionkey)";
MaterializedResult result = computeActual("explain(type distributed) " + testQuery);
assertEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(testQuery);
assertEquals(result.getRowCount(), 25);

// With feature
Session session = Session.builder(getSession())
.setSystemProperty(JOIN_PREFILTER_BUILD_SIDE, String.valueOf(true))
.build();
result = computeActual(session, "explain(type distributed) " + testQuery);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(session, testQuery);
assertEquals(result.getRowCount(), 25);
}

{
// Orig
@Language("SQL") String testQuery = "SELECT 1 from region r join nation n on cast(r.regionkey as varchar) = cast(n.regionkey as varchar)";
MaterializedResult result = computeActual("explain(type distributed) " + testQuery);
assertEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(testQuery);
assertEquals(result.getRowCount(), 25);

// With feature
Session session = Session.builder(getSession())
.setSystemProperty(JOIN_PREFILTER_BUILD_SIDE, String.valueOf(true))
.setSystemProperty(REMOVE_REDUNDANT_CAST_TO_VARCHAR_IN_JOIN, String.valueOf(false))
.build();
result = computeActual(session, "explain(type distributed) " + testQuery);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("XX_HASH_64"), -1);
result = computeActual(session, testQuery);
assertEquals(result.getRowCount(), 25);
}

{
// Orig
String testQuery = "SELECT 1 from lineitem l join orders o on l.orderkey = o.orderkey and l.suppkey = o.custkey";
MaterializedResult result = computeActual("explain(type distributed) " + testQuery);
assertEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
result = computeActual(testQuery);
assertEquals(result.getRowCount(), 37);

// With feature
Session session = Session.builder(getSession())
.setSystemProperty(JOIN_PREFILTER_BUILD_SIDE, String.valueOf(true))
.build();
result = computeActual(session, "explain(type distributed) " + testQuery);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("SemiJoin"), -1);
assertNotEquals(((String) result.getMaterializedRows().get(0).getField(0)).indexOf("XX_HASH_64"), -1);
result = computeActual(session, testQuery);
assertEquals(result.getRowCount(), 37);
}
}

@Test
Expand Down