org.apache.calcite.adapter.enumerable

Class EnumerableMergeJoin

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.BiRel

org.apache.calcite.rel.core.Join

org.apache.calcite.adapter.enumerable.EnumerableMergeJoin

All Implemented Interfaces:

Cloneable, EnumerableRel, RelOptNode, Hintable, PhysicalNode, RelNode

public class EnumerableMergeJoin
extends Join
implements EnumerableRel

Implementation of Join in enumerable calling convention using a merge algorithm.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.calcite.adapter.enumerable.EnumerableRel

EnumerableRel.Prefer, EnumerableRel.Result

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

RelNode.Context

Field Summary

Fields inherited from class org.apache.calcite.rel.core.Join

condition, hints, joinInfo, joinType, variablesSet

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	EnumerableMergeJoin(RelOptCluster cluster, RelTraitSet traits, RelNode left, RelNode right, RexNode condition, Set<CorrelationId> variablesSet, JoinRelType joinType)

Method Summary

Modifier and Type	Method and Description
@Nullable RelOptCost	computeSelfCost(RelOptPlanner planner, RelMetadataQuery mq) Returns the cost of this plan (not including children).
EnumerableMergeJoin	copy(RelTraitSet traitSet, RexNode condition, RelNode left, RelNode right, JoinRelType joinType, boolean semiJoinDone) Creates a copy of this join, overriding condition, system fields and inputs.
static EnumerableMergeJoin	create(RelNode left, RelNode right, RexNode condition, ImmutableIntList leftKeys, ImmutableIntList rightKeys, JoinRelType joinType)
@Nullable Pair<RelTraitSet,List<RelTraitSet>>	deriveTraits(RelTraitSet childTraits, int childId) Derive traitset from child node, returns a pair of traits after traits derivation.
DeriveMode	getDeriveMode() Returns mode of derivation.
EnumerableRel.Result	implement(EnumerableRelImplementor implementor, EnumerableRel.Prefer pref) Creates a plan for this expression according to a calling convention.
static boolean	isMergeJoinSupported(JoinRelType joinType)
@Nullable Pair<RelTraitSet,List<RelTraitSet>>	passThroughTraits(RelTraitSet required) Pass collations through can have three cases: 1.

Methods inherited from class org.apache.calcite.rel.core.Join

accept, analyzeCondition, copy, createJoinType, deepEquals0, deepHashCode0, deriveJoinRowType, deriveRowType, estimateJoinedRows, estimateRowCount, explainTerms, getCondition, getHints, getJoinType, getSystemFieldList, getVariablesSet, isSemiJoin, isSemiJoinDone, isValid

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

childrenAccept, getInputs, getLeft, getRight, replaceInput

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

accept, collectVariablesSet, collectVariablesUsed, deepEquals, deepHashCode, equals, explain, getCluster, getConvention, getCorrelVariable, 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.PhysicalNode

derive, derive, passThrough

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

accept, accept, childrenAccept, collectVariablesSet, collectVariablesUsed, copy, deepEquals, deepHashCode, estimateRowCount, explain, explain, fieldIsNullable, getConvention, getCorrelVariable, getDigest, getExpectedInputRowType, getInput, getInputs, getRelDigest, getRelTypeName, getRowType, getTable, getVariablesSet, isEnforcer, isValid, metadata, onRegister, recomputeDigest, register, replaceInput

Methods inherited from interface org.apache.calcite.plan.RelOptNode

getCluster, getDescription, getId, getTraitSet

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

attachHints, withHints

Constructor Detail

EnumerableMergeJoin

protected EnumerableMergeJoin(RelOptCluster cluster,
                              RelTraitSet traits,
                              RelNode left,
                              RelNode right,
                              RexNode condition,
                              Set<CorrelationId> variablesSet,
                              JoinRelType joinType)

Method Detail

isMergeJoinSupported

public static boolean isMergeJoinSupported(JoinRelType joinType)

passThroughTraits

public @Nullable Pair<RelTraitSet,List<RelTraitSet>> passThroughTraits(RelTraitSet required)

Pass collations through can have three cases: 1. If sort keys are equal to either left join keys, or right join keys, collations can be pushed to both join sides with correct mappings. For example, for the query select * from foo join bar on foo.a=bar.b order by foo.a desc after traits pass through it will be equivalent to select * from (select * from foo order by foo.a desc) join (select * from bar order by bar.b desc) 2. If sort keys are sub-set of either left join keys, or right join keys, collations have to be extended to cover all joins keys before passing through, because merge join requires all join keys are sorted. For example, for the query select * from foo join bar on foo.a=bar.b and foo.c=bar.d order by foo.a desc after traits pass through it will be equivalent to select * from (select * from foo order by foo.a desc, foo.c) join (select * from bar order by bar.b desc, bar.d) 3. If sort keys are super-set of either left join keys, or right join keys, but not both, collations can be completely passed to the join key whose join keys match the prefix of collations. Meanwhile, partial mapped collations can be passed to another join side to make sure join keys are sorted. For example, for the query select * from foo join bar on foo.a=bar.b and foo.c=bar.d order by foo.a desc, foo.c desc, foo.e after traits pass through it will be equivalent to select * from (select * from foo order by foo.a desc, foo.c desc, foo.e) join (select * from bar order by bar.b desc, bar.d desc)

Specified by:

passThroughTraits in interface EnumerableRel

Specified by:

passThroughTraits in interface PhysicalNode

deriveTraits

public @Nullable Pair<RelTraitSet,List<RelTraitSet>> deriveTraits(RelTraitSet childTraits,
                                                                  int childId)

Description copied from interface: PhysicalNode

Derive traitset from child node, returns a pair of traits after traits derivation.

Pair.left: the new traitset

Pair.right: the list of required traitsets for child nodes

Specified by:

deriveTraits in interface EnumerableRel

Specified by:

deriveTraits in interface PhysicalNode

getDeriveMode

public DeriveMode getDeriveMode()

Description copied from interface: PhysicalNode

Returns mode of derivation.

Specified by:

getDeriveMode in interface EnumerableRel

Specified by:

getDeriveMode in interface PhysicalNode

create

public static EnumerableMergeJoin create(RelNode left,
                                         RelNode right,
                                         RexNode condition,
                                         ImmutableIntList leftKeys,
                                         ImmutableIntList rightKeys,
                                         JoinRelType joinType)

copy

public EnumerableMergeJoin copy(RelTraitSet traitSet,
                                RexNode condition,
                                RelNode left,
                                RelNode right,
                                JoinRelType joinType,
                                boolean semiJoinDone)

Description copied from class: Join

Creates a copy of this join, overriding condition, system fields and inputs.

General contract as RelNode.copy(org.apache.calcite.plan.RelTraitSet, java.util.List<org.apache.calcite.rel.RelNode>).

Specified by:

copy in class Join

Parameters:

traitSet - Traits

condition - Condition

left - Left input

right - Right input

joinType - Join type

semiJoinDone - Whether this join has been translated to a semi-join

Returns:

Copy of this join

computeSelfCost

public @Nullable RelOptCost computeSelfCost(RelOptPlanner planner,
                                            RelMetadataQuery mq)

Description copied from interface: RelNode

Returns the cost of this plan (not including children). The base implementation throws an error; derived classes should override.

NOTE jvs 29-Mar-2006: Don't call this method directly. Instead, use RelMetadataQuery.getNonCumulativeCost(org.apache.calcite.rel.RelNode), which gives plugins a chance to override the rel's default ideas about cost.

Specified by:

computeSelfCost in interface RelNode

Overrides:

computeSelfCost in class Join

Parameters:

planner - Planner for cost calculation

mq - Metadata query

Returns:

Cost of this plan (not including children)

implement

public EnumerableRel.Result implement(EnumerableRelImplementor implementor,
                                      EnumerableRel.Prefer pref)

Description copied from interface: EnumerableRel

Creates a plan for this expression according to a calling convention.

Specified by:

implement in interface EnumerableRel

Parameters:

implementor - Implementor

pref - Preferred representation for rows in result expression

Returns:

Plan for this expression according to a calling convention