net.sf.farrago.fennel.rel
Class FennelPullCollectRel

java.lang.Object
  org.eigenbase.rel.AbstractRelNode
      org.eigenbase.rel.SingleRel
          net.sf.farrago.fennel.rel.FennelSingleRel
              net.sf.farrago.fennel.rel.FennelPullCollectRel

All Implemented Interfaces:

Cloneable, FennelRel, RelNode

public class FennelPullCollectRel
extends FennelSingleRel

FennelPullCollectRel is the relational expression corresponding to a collect implemented inside of Fennel.

Rules:

• FennelCollectRule creates this from a CollectRel.

Since:

Dec 11, 2004

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/fennel/rel/FennelPullCollectRel.java#1 $

Author:

Wael Chatila

Field Summary

(package private) String

fieldName

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

FennelPullCollectRel(RelOptCluster cluster, RelNode child, String fieldName)
Creates a FennelPullCollectRel.

Method Summary

FennelPullCollectRel	clone() Clones this RelNode.
RelOptCost	computeSelfCost(RelOptPlanner planner) Returns the cost of this plan (not including children).
protected RelDataType	deriveRowType()
FemExecutionStreamDef	toStreamDef(FennelRelImplementor implementor) Converts this relational expression to FemExecutionStreamDef form.

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

getCollations, getFarragoTypeFactory, implementFennelChild

Methods inherited from class org.eigenbase.rel.SingleRel

childrenAccept, explain, getChild, getInputs, getRows, replaceInput

Methods inherited from class org.eigenbase.rel.AbstractRelNode

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, explain, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getInputs, getOrCreateCorrelVariable, getQuery, getRelTypeName, getRows, getRowType, getTable, getTraits, getVariablesStopped, isAccessTo, isDistinct, isValid, onRegister, recomputeDigest, registerCorrelVariable, replaceInput, setCorrelVariable

Field Detail

fieldName

final String fieldName

Constructor Detail

FennelPullCollectRel

public FennelPullCollectRel(RelOptCluster cluster,
                            RelNode child,
                            String fieldName)

Creates a FennelPullCollectRel.

Parameters:

cluster - Cluster

child - Child relational expression

fieldName - Name of the sole output field

Method Detail

deriveRowType

protected RelDataType deriveRowType()

Overrides:

deriveRowType in class SingleRel

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

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

clone

public FennelPullCollectRel 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