net.sf.farrago.fennel.rel
Class LhxJoinRel

java.lang.Object
  org.eigenbase.rel.AbstractRelNode
      net.sf.farrago.fennel.rel.FennelDoubleRel
          net.sf.farrago.fennel.rel.LhxJoinRel

All Implemented Interfaces:

Cloneable, FennelRel, RelNode

public class LhxJoinRel
extends FennelDoubleRel

LhxJoinRel implements the hash join.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/fennel/rel/LhxJoinRel.java#3 $

Author:

Rushan Chen

Field Summary

(package private) long	cndBuildKey cardinality of the build key
(package private) List<Integer>	filterNulls Whether the join key at a given position matches null values
(package private) boolean	isSetop This LhxJoinRel implements setop, one of the following: intersect (distinct), except (distinct) Setop differs from regular join in its treatment of NULLs and duplicates: NULLs are considered "matching" and duplicates are removed by default(the default setop is setop DISTINCT).
private LhxJoinRelType	joinType Join type.
(package private) List<Integer>	leftKeys Join key columns from the left.
(package private) long	numBuildRows row count on the build side
(package private) List<Integer>	rightKeys Join key columns from the right.

Fields inherited from class net.sf.farrago.fennel.rel.FennelDoubleRel

left, right

Fields inherited from class org.eigenbase.rel.AbstractRelNode

digest, id, rowType, traits

Fields inherited from interface net.sf.farrago.query.FennelRel

FENNEL_EXEC_CONVENTION

Fields inherited from interface org.eigenbase.rel.RelNode

emptyArray

Constructor Summary

LhxJoinRel(RelOptCluster cluster, RelNode left, RelNode right, LhxJoinRelType joinType, boolean isSetop, List<Integer> leftKeys, List<Integer> rightKeys, List<Integer> filterNulls, List<String> fieldNameList, long numBuildRows, long cndBuildKey)
Creates a new LhxJoinRel object.

Method Summary

LhxJoinRel	clone() Clones this RelNode.
RelOptCost	computeSelfCost(RelOptPlanner planner) Returns the cost of this plan (not including children).
protected RelDataType	deriveRowType()
void	explain(RelOptPlanWriter pw)
LhxJoinRelType	getJoinType()
RelNode	getLeft()
List<Integer>	getLeftKeys()
RelNode	getRight()
List<Integer>	getRightKeys()
double	getRows() Returns an estimate of the number of rows this relational expression will return.
FemExecutionStreamDef	toStreamDef(FennelRelImplementor implementor) Converts this relational expression to FemExecutionStreamDef form.

Methods inherited from class net.sf.farrago.fennel.rel.FennelDoubleRel

getCollations, getFarragoTypeFactory, getInputs, implementFennelChild, replaceInput

Methods inherited from class org.eigenbase.rel.AbstractRelNode

childrenAccept, cloneTraits, collectVariablesSet, collectVariablesUsed, computeDigest, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getOrCreateCorrelVariable, getQuery, getRelTypeName, getRowType, getTable, getTraits, getVariablesStopped, inheritTraitsFrom, isAccessTo, isDistinct, isValid, onRegister, recomputeDigest, register, registerCorrelVariable, setCorrelVariable, toString

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.eigenbase.rel.RelNode

childrenAccept, collectVariablesSet, collectVariablesUsed, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getOrCreateCorrelVariable, getQuery, getRelTypeName, getRowType, getTable, getTraits, getVariablesStopped, isAccessTo, isDistinct, isValid, onRegister, recomputeDigest, registerCorrelVariable, setCorrelVariable

Field Detail

joinType

private final LhxJoinRelType joinType

Join type. Currently only inner join is supported.

leftKeys

List<Integer> leftKeys

Join key columns from the left.

rightKeys

List<Integer> rightKeys

Join key columns from the right.

filterNulls

List<Integer> filterNulls

Whether the join key at a given position matches null values

numBuildRows

long numBuildRows

row count on the build side

cndBuildKey

long cndBuildKey

cardinality of the build key

isSetop

boolean isSetop

This LhxJoinRel implements setop, one of the following: intersect (distinct), except (distinct) Setop differs from regular join in its treatment of NULLs and duplicates: NULLs are considered "matching" and duplicates are removed by default(the default setop is setop DISTINCT).

Constructor Detail

LhxJoinRel

public LhxJoinRel(RelOptCluster cluster,
                  RelNode left,
                  RelNode right,
                  LhxJoinRelType joinType,
                  boolean isSetop,
                  List<Integer> leftKeys,
                  List<Integer> rightKeys,
                  List<Integer> filterNulls,
                  List<String> fieldNameList,
                  long numBuildRows,
                  long cndBuildKey)

Creates a new LhxJoinRel object.

Parameters:

cluster - RelOptCluster for this rel

left - left input

right - right input

fieldNameList - If not null, the row type will have these field names

Method Detail

clone

public LhxJoinRel clone()

Description copied from interface: RelNode

Clones this RelNode.

Traits of the RelNode must be explicitly cloned, using AbstractRelNode.inheritTraitsFrom(AbstractRelNode), as the RelNode may have traits of which it has no knowledge. Example implementation:

     public MyRelNode clone()
     {
         MyRelNode clone = new MyRelNode(...);
         clone.inheritTraitsFrom(this);
         return clone;
     }
 

N.B.: This method must be overridden whenever an existing, concrete RelNode is extended. Otherwise, calling clone() will produce a differently typed RelNode, resulting in invalid or incorrect query plans.

Specified by:

clone in interface RelNode

Specified by:

clone in class AbstractRelNode

Returns:

a clone of this RelNode

computeSelfCost

public RelOptCost computeSelfCost(RelOptPlanner planner)

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.eigenbase.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 AbstractRelNode

getRows

public double getRows()

Description copied from interface: RelNode

Returns an estimate of the number of rows this relational expression will return.

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

Specified by:

getRows in interface RelNode

Overrides:

getRows in class AbstractRelNode

explain

public void explain(RelOptPlanWriter pw)

Specified by:

explain in interface RelNode

Overrides:

explain in class AbstractRelNode

deriveRowType

protected RelDataType deriveRowType()

Overrides:

deriveRowType in class FennelDoubleRel

toStreamDef

public FemExecutionStreamDef toStreamDef(FennelRelImplementor implementor)

Description copied from interface: FennelRel

Converts this relational expression to FemExecutionStreamDef form. In the process, the relational expression will almost certainly call FennelRelImplementor.visitFennelChild(net.sf.farrago.query.FennelRel, int) on each of its children.

Parameters:

implementor - for generating Java code

Returns:

generated FemExecutionStreamDef

getJoinType

public LhxJoinRelType getJoinType()

getLeft

public RelNode getLeft()

getRight

public RelNode getRight()

getLeftKeys

public List<Integer> getLeftKeys()

getRightKeys

public List<Integer> getRightKeys()