org.eigenbase.rel
Class AggregateRelBase

java.lang.Object
  org.eigenbase.rel.AbstractRelNode
      org.eigenbase.rel.SingleRel
          org.eigenbase.rel.AggregateRelBase

All Implemented Interfaces:

Cloneable, RelNode

Direct Known Subclasses:

AggregateRel, FennelAggRel, LhxAggRel

public abstract class AggregateRelBase
extends SingleRel

AggregateRelBase is an abstract base class for implementations of AggregateRel.

Version:

$Id: //open/dev/farrago/src/org/eigenbase/rel/AggregateRelBase.java#21 $

Author:

John V. Sichi

Nested Class Summary

static class

AggregateRelBase.AggCallBinding Implementation of the SqlOperatorBinding interface for an aggregate call applied to a set of operands in the context of a AggregateRel.

Field Summary

protected List<AggregateCall>	aggCalls
protected int	groupCount

Fields inherited from class org.eigenbase.rel.AbstractRelNode

digest, id, nextId, rowType, traits

Fields inherited from interface org.eigenbase.rel.RelNode

emptyArray

Constructor Summary

protected

AggregateRelBase(RelOptCluster cluster, RelTraitSet traits, RelNode child, int groupCount, List<AggregateCall> aggCalls) Creates an AggregateRelBase.

Method Summary

RelOptCost	computeSelfCost(RelOptPlanner planner) Returns the cost of this plan (not including children).
boolean	containsDistinctCall() Returns whether any of the aggregates are DISTINCT.
protected RelDataType	deriveRowType()
void	explain(RelOptPlanWriter pw)
List<AggregateCall>	getAggCallList() Returns a list of calls to aggregate functions.
int	getGroupCount() Returns the number of grouping fields.
double	getRows() Returns an estimate of the number of rows this relational expression will return.
boolean	isDistinct() Returns whether the same value will not come out twice.
private boolean	typeMatchesInferred(AggregateCall aggCall, boolean fail) Returns whether the inferred type of an AggregateCall matches the type it was given when it was created.

Methods inherited from class org.eigenbase.rel.SingleRel

childrenAccept, getChild, getInputs, replaceInput

Methods inherited from class org.eigenbase.rel.AbstractRelNode

clone, 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

Field Detail

aggCalls

protected List<AggregateCall> aggCalls

groupCount

protected int groupCount

Constructor Detail

AggregateRelBase

protected AggregateRelBase(RelOptCluster cluster,
                           RelTraitSet traits,
                           RelNode child,
                           int groupCount,
                           List<AggregateCall> aggCalls)

Creates an AggregateRelBase.

Parameters:

cluster - Cluster

traits - Traits

child - Child

groupCount - Size of grouping key

aggCalls - Collection of calls to aggregate functions

Method Detail

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

getAggCallList

public List<AggregateCall> getAggCallList()

Returns a list of calls to aggregate functions.

Returns:

list of calls to aggregate functions

getGroupCount

public int getGroupCount()

Returns the number of grouping fields. These fields are the leading fields in both the input and output records.

Returns:

number of grouping fields

explain

public void explain(RelOptPlanWriter pw)

Specified by:

explain in interface RelNode

Overrides:

explain in class SingleRel

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

deriveRowType

protected RelDataType deriveRowType()

Overrides:

deriveRowType in class SingleRel

typeMatchesInferred

private boolean typeMatchesInferred(AggregateCall aggCall,
                                    boolean fail)

Returns whether the inferred type of an AggregateCall matches the type it was given when it was created.

Parameters:

aggCall - Aggregate call

fail - Whether to fail if the types do not match

Returns:

Whether the inferred and declared types match

containsDistinctCall

public boolean containsDistinctCall()

Returns whether any of the aggregates are DISTINCT.