org.apache.calcite.rel.core

Class Correlate

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.BiRel

org.apache.calcite.rel.core.Correlate

All Implemented Interfaces:

Cloneable, org.apache.calcite.plan.RelOptNode, org.apache.calcite.rel.hint.Hintable, org.apache.calcite.rel.RelNode

Direct Known Subclasses:

LogicalCorrelate

public abstract class Correlate
extends org.apache.calcite.rel.BiRel
implements org.apache.calcite.rel.hint.Hintable

A relational operator that performs nested-loop joins.

Temporarily copy from calcite to cherry-pick [CALCITE-5107] and will be removed when upgrade the latest calcite.

It behaves like a kind of Join, but works by setting variables in its environment and restarting its right-hand input.

Correlate is not a join since: typical rules should not match Correlate.

A Correlate is used to represent a correlated query. One implementation strategy is to de-correlate the expression.

Mapping of physical operations to logical ones

Physical operation	Logical operation
NestedLoops	Correlate(A, B, regular)
NestedLoopsOuter	Correlate(A, B, outer)
NestedLoopsSemi	Correlate(A, B, semi)
NestedLoopsAnti	Correlate(A, B, anti)
HashJoin	EquiJoin(A, B)
HashJoinOuter	EquiJoin(A, B, outer)
HashJoinSemi	SemiJoin(A, B, semi)
HashJoinAnti	SemiJoin(A, B, anti)

See Also:

CorrelationId

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.calcite.rel.RelNode

org.apache.calcite.rel.RelNode.Context

Field Summary

Fields

Modifier and Type	Field and Description
protected org.apache.calcite.rel.core.CorrelationId	correlationId
protected com.google.common.collect.ImmutableList<org.apache.calcite.rel.hint.RelHint>	hints
protected org.apache.calcite.rel.core.JoinRelType	joinType
protected org.apache.calcite.util.ImmutableBitSet	requiredColumns

Fields inherited from class org.apache.calcite.rel.BiRel

left, right

Fields inherited from class org.apache.calcite.rel.AbstractRelNode

digest, id, rowType, traitSet

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Correlate(org.apache.calcite.rel.RelInput input) Creates a Correlate by parsing serialized output.
protected	Correlate(org.apache.calcite.plan.RelOptCluster cluster, org.apache.calcite.plan.RelTraitSet traitSet, List<org.apache.calcite.rel.hint.RelHint> hints, org.apache.calcite.rel.RelNode left, org.apache.calcite.rel.RelNode right, org.apache.calcite.rel.core.CorrelationId correlationId, org.apache.calcite.util.ImmutableBitSet requiredColumns, org.apache.calcite.rel.core.JoinRelType joinType) Creates a Correlate.
protected	Correlate(org.apache.calcite.plan.RelOptCluster cluster, org.apache.calcite.plan.RelTraitSet traitSet, org.apache.calcite.rel.RelNode left, org.apache.calcite.rel.RelNode right, org.apache.calcite.rel.core.CorrelationId correlationId, org.apache.calcite.util.ImmutableBitSet requiredColumns, org.apache.calcite.rel.core.JoinRelType joinType) Creates a Correlate.

Method Summary

Modifier and Type	Method and Description
@Nullable org.apache.calcite.plan.RelOptCost	computeSelfCost(org.apache.calcite.plan.RelOptPlanner planner, org.apache.calcite.rel.metadata.RelMetadataQuery mq)
Correlate	copy(org.apache.calcite.plan.RelTraitSet traitSet, List<org.apache.calcite.rel.RelNode> inputs)
abstract Correlate	copy(org.apache.calcite.plan.RelTraitSet traitSet, org.apache.calcite.rel.RelNode left, org.apache.calcite.rel.RelNode right, org.apache.calcite.rel.core.CorrelationId correlationId, org.apache.calcite.util.ImmutableBitSet requiredColumns, org.apache.calcite.rel.core.JoinRelType joinType)
protected org.apache.calcite.rel.type.RelDataType	deriveRowType()
double	estimateRowCount(org.apache.calcite.rel.metadata.RelMetadataQuery mq)
org.apache.calcite.rel.RelWriter	explainTerms(org.apache.calcite.rel.RelWriter pw)
org.apache.calcite.rel.core.CorrelationId	getCorrelationId() Returns the correlating expressions.
String	getCorrelVariable()
com.google.common.collect.ImmutableList<org.apache.calcite.rel.hint.RelHint>	getHints()
org.apache.calcite.rel.core.JoinRelType	getJoinType()
org.apache.calcite.util.ImmutableBitSet	getRequiredColumns() Returns the required columns in left relation required for the correlation in the right.
Set<org.apache.calcite.rel.core.CorrelationId>	getVariablesSet()
boolean	isValid(org.apache.calcite.util.Litmus litmus, org.apache.calcite.rel.RelNode.Context context)

Methods inherited from class org.apache.calcite.rel.BiRel

childrenAccept, getInputs, getLeft, getRight, replaceInput

Methods inherited from class org.apache.calcite.rel.AbstractRelNode

accept, accept, collectVariablesSet, collectVariablesUsed, deepEquals, deepHashCode, equals, explain, getCluster, getConvention, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getRelDigest, getRelTypeName, getRowType, getTable, getTraitSet, hashCode, isEnforcer, metadata, onRegister, recomputeDigest, register, sole, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.calcite.rel.hint.Hintable

attachHints, withHints

Methods inherited from interface org.apache.calcite.rel.RelNode

explain, fieldIsNullable

Field Detail

correlationId

protected final org.apache.calcite.rel.core.CorrelationId correlationId

requiredColumns

protected final org.apache.calcite.util.ImmutableBitSet requiredColumns

joinType

protected final org.apache.calcite.rel.core.JoinRelType joinType

hints

protected final com.google.common.collect.ImmutableList<org.apache.calcite.rel.hint.RelHint> hints

Constructor Detail

Correlate

protected Correlate(org.apache.calcite.plan.RelOptCluster cluster,
                    org.apache.calcite.plan.RelTraitSet traitSet,
                    List<org.apache.calcite.rel.hint.RelHint> hints,
                    org.apache.calcite.rel.RelNode left,
                    org.apache.calcite.rel.RelNode right,
                    org.apache.calcite.rel.core.CorrelationId correlationId,
                    org.apache.calcite.util.ImmutableBitSet requiredColumns,
                    org.apache.calcite.rel.core.JoinRelType joinType)

Creates a Correlate.

Parameters:

cluster - Cluster this relational expression belongs to

hints - Hints for this node

left - Left input relational expression

right - Right input relational expression

correlationId - Variable name for the row of left input

requiredColumns - Set of columns that are used by correlation

joinType - Join type

Correlate

protected Correlate(org.apache.calcite.plan.RelOptCluster cluster,
                    org.apache.calcite.plan.RelTraitSet traitSet,
                    org.apache.calcite.rel.RelNode left,
                    org.apache.calcite.rel.RelNode right,
                    org.apache.calcite.rel.core.CorrelationId correlationId,
                    org.apache.calcite.util.ImmutableBitSet requiredColumns,
                    org.apache.calcite.rel.core.JoinRelType joinType)

Creates a Correlate.

Parameters:

cluster - Cluster this relational expression belongs to

left - Left input relational expression

right - Right input relational expression

correlationId - Variable name for the row of left input

requiredColumns - Set of columns that are used by correlation

joinType - Join type

Correlate

protected Correlate(org.apache.calcite.rel.RelInput input)

Creates a Correlate by parsing serialized output.

Parameters:

input - Input representation

Method Detail

isValid

public boolean isValid(org.apache.calcite.util.Litmus litmus,
                       org.apache.calcite.rel.RelNode.Context context)

Specified by:

isValid in interface org.apache.calcite.rel.RelNode

Overrides:

isValid in class org.apache.calcite.rel.AbstractRelNode

copy

public Correlate copy(org.apache.calcite.plan.RelTraitSet traitSet,
                      List<org.apache.calcite.rel.RelNode> inputs)

Specified by:

copy in interface org.apache.calcite.rel.RelNode

Overrides:

copy in class org.apache.calcite.rel.AbstractRelNode

copy

public abstract Correlate copy(org.apache.calcite.plan.RelTraitSet traitSet,
                               org.apache.calcite.rel.RelNode left,
                               org.apache.calcite.rel.RelNode right,
                               org.apache.calcite.rel.core.CorrelationId correlationId,
                               org.apache.calcite.util.ImmutableBitSet requiredColumns,
                               org.apache.calcite.rel.core.JoinRelType joinType)

getJoinType

public org.apache.calcite.rel.core.JoinRelType getJoinType()

deriveRowType

protected org.apache.calcite.rel.type.RelDataType deriveRowType()

Overrides:

deriveRowType in class org.apache.calcite.rel.AbstractRelNode

explainTerms

public org.apache.calcite.rel.RelWriter explainTerms(org.apache.calcite.rel.RelWriter pw)

Overrides:

explainTerms in class org.apache.calcite.rel.BiRel

getCorrelationId

public org.apache.calcite.rel.core.CorrelationId getCorrelationId()

Returns the correlating expressions.

Returns:

correlating expressions

getCorrelVariable

public String getCorrelVariable()

Specified by:

getCorrelVariable in interface org.apache.calcite.rel.RelNode

Overrides:

getCorrelVariable in class org.apache.calcite.rel.AbstractRelNode

getRequiredColumns

public org.apache.calcite.util.ImmutableBitSet getRequiredColumns()

Returns the required columns in left relation required for the correlation in the right.

Returns:

columns in left relation required for the correlation in the right

getVariablesSet

public Set<org.apache.calcite.rel.core.CorrelationId> getVariablesSet()

Specified by:

getVariablesSet in interface org.apache.calcite.rel.RelNode

Overrides:

getVariablesSet in class org.apache.calcite.rel.AbstractRelNode

estimateRowCount

public double estimateRowCount(org.apache.calcite.rel.metadata.RelMetadataQuery mq)

Specified by:

estimateRowCount in interface org.apache.calcite.rel.RelNode

Overrides:

estimateRowCount in class org.apache.calcite.rel.AbstractRelNode

computeSelfCost

public @Nullable org.apache.calcite.plan.RelOptCost computeSelfCost(org.apache.calcite.plan.RelOptPlanner planner,
                                                                    org.apache.calcite.rel.metadata.RelMetadataQuery mq)

Specified by:

computeSelfCost in interface org.apache.calcite.rel.RelNode

Overrides:

computeSelfCost in class org.apache.calcite.rel.AbstractRelNode

getHints

public com.google.common.collect.ImmutableList<org.apache.calcite.rel.hint.RelHint> getHints()

Specified by:

getHints in interface org.apache.calcite.rel.hint.Hintable