net.sf.farrago.fennel.rel
Class FennelSortRel

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

All Implemented Interfaces:

Cloneable, FennelRel, RelNode

public class FennelSortRel
extends FennelSingleRel

FennelSortRel is the relational expression corresponding to a sort implemented inside of Fennel.

Version:

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

Author:

John V. Sichi

Field Summary

private RelFieldCollation[]	collations
private boolean	discardDuplicates Whether to discard tuples with duplicate keys.

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

FennelSortRel(RelOptCluster cluster, RelNode child, Integer[] keyProjection, boolean discardDuplicates)
Creates a new FennelSortRel object.

FennelSortRel(RelOptCluster cluster, RelNode child, RelFieldCollation[] collations, boolean discardDuplicates)
Creates a new FennelSortRel object.

Method Summary

FennelSortRel	clone() Clones this RelNode.
RelOptCost	computeSelfCost(RelOptPlanner planner) Returns the cost of this plan (not including children).
private static RelFieldCollation[]	convertKeyProjection(Integer[] keyProjection)
void	explain(RelOptPlanWriter pw)
RelFieldCollation[]	getCollations() TODO: jhyde, 2006/3/28: unify with RelNode.getCollationList()
double	getRows() Returns an estimate of the number of rows this relational expression will return.
boolean	isDiscardDuplicates()
boolean	isDistinct() Returns whether the same value will not come out twice.
FemExecutionStreamDef	toStreamDef(FennelRelImplementor implementor) Converts this relational expression to FemExecutionStreamDef form.

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

getFarragoTypeFactory, implementFennelChild

Methods inherited from class org.eigenbase.rel.SingleRel

childrenAccept, deriveRowType, getChild, getInputs, 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, 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, getInputs, getOrCreateCorrelVariable, getQuery, getRelTypeName, getRowType, getTable, getTraits, getVariablesStopped, isAccessTo, isValid, onRegister, recomputeDigest, registerCorrelVariable, replaceInput, setCorrelVariable

Field Detail

collations

private final RelFieldCollation[] collations

discardDuplicates

private final boolean discardDuplicates

Whether to discard tuples with duplicate keys.

Constructor Detail

FennelSortRel

public FennelSortRel(RelOptCluster cluster,
                     RelNode child,
                     Integer[] keyProjection,
                     boolean discardDuplicates)

Creates a new FennelSortRel object.

Parameters:

cluster - RelOptCluster for this rel

child - rel producing rows to be sorted

keyProjection - 0-based ordinals of fields making up sort key (all ascending)

discardDuplicates - whether to discard duplicates based on key

FennelSortRel

public FennelSortRel(RelOptCluster cluster,
                     RelNode child,
                     RelFieldCollation[] collations,
                     boolean discardDuplicates)

Creates a new FennelSortRel object.

Parameters:

cluster - RelOptCluster for this rel

child - rel producing rows to be sorted

collations - array of sort specifications

discardDuplicates - whether to discard duplicates based on key

Method Detail

convertKeyProjection

private static RelFieldCollation[] convertKeyProjection(Integer[] keyProjection)

isDistinct

public boolean isDistinct()

Description copied from interface: RelNode

Returns whether the same value will not come out twice. Default value is false, derived classes should override.

Specified by:

isDistinct in interface RelNode

Overrides:

isDistinct in class AbstractRelNode

isDiscardDuplicates

public boolean isDiscardDuplicates()

clone

public FennelSortRel 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

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 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

explain

public void explain(RelOptPlanWriter pw)

Specified by:

explain in interface RelNode

Overrides:

explain in class SingleRel

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

getCollations

public RelFieldCollation[] getCollations()

Description copied from interface: FennelRel

TODO: jhyde, 2006/3/28: unify with RelNode.getCollationList()

Specified by:

getCollations in interface FennelRel

Overrides:

getCollations in class FennelSingleRel

Returns:

the sort order produced by this FennelRel, or an empty array if the output is not guaranteed to be in any particular order.