Class FennelPullCollectRel

  extended by org.eigenbase.rel.AbstractRelNode
      extended by org.eigenbase.rel.SingleRel
          extended by net.sf.farrago.fennel.rel.FennelSingleRel
              extended by 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.


Dec 11, 2004
$Id: //open/dev/farrago/src/net/sf/farrago/fennel/rel/ $
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
Fields inherited from interface org.eigenbase.rel.RelNode
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


final String fieldName
Constructor Detail


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

cluster - Cluster
child - Child relational expression
fieldName - Name of the sole output field
Method Detail


protected RelDataType deriveRowType()
deriveRowType in class SingleRel


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
computeSelfCost in class AbstractRelNode


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.

implementor - for generating Java code
generated FemExecutionStreamDef


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(...);
         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
a clone of this RelNode