net.sf.saffron.rel
Class AggregateRel

java.lang.Object
  |
  +--net.sf.saffron.rel.SaffronRel
        |
        +--net.sf.saffron.rel.SingleRel
              |
              +--net.sf.saffron.rel.AggregateRel

Direct Known Subclasses:

JavaAggregateRel

public class AggregateRel

extends SingleRel

AggregateRel is a relational operator which eliminates duplicates and computes totals.

Since:

3 February, 2002

Version:

$Id: //open/saffron/src/net/sf/saffron/rel/AggregateRel.java#4 $

Author:

jhyde

Nested Class Summary

static class

AggregateRel.Call

Field Summary

protected AggregateRel.Call[]	aggCalls
protected int	groupCount

Fields inherited from class net.sf.saffron.rel.SingleRel

child

Fields inherited from class net.sf.saffron.rel.SaffronRel

cluster, digest, emptyArray, id, nextId, rowType

Constructor Summary

AggregateRel(VolcanoCluster cluster, SaffronRel child, int groupCount, AggregateRel.Call[] aggCalls)

Method Summary

Object	clone()
PlanCost	computeSelfCost(SaffronPlanner planner) Returns the cost of this plan (not including children).
protected SaffronType	deriveRowType()
AggregateRel.Call[]	getAggCalls()
int	getGroupCount()

Methods inherited from class net.sf.saffron.rel.SingleRel

childrenAccept, explain, getInputs, getRows, replaceInput

Methods inherited from class net.sf.saffron.rel.SaffronRel

computeDigest, getChildExps, getCluster, getConvention, getCorrelVariable, getId, getInput, getOrCreateCorrelVariable, getQualifier, getQuery, getRelTypeName, getRowType, getTable, getVariablesStopped, implement, implementFieldAccess, isAccessTo, isDistinct, 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 AggregateRel.Call[] aggCalls

groupCount

protected int groupCount

Constructor Detail

AggregateRel

public AggregateRel(VolcanoCluster cluster,
                    SaffronRel child,
                    int groupCount,
                    AggregateRel.Call[] aggCalls)

Method Detail

getAggCalls

public AggregateRel.Call[] getAggCalls()

getGroupCount

public int getGroupCount()

clone

public Object clone()

Specified by:

clone in class SaffronRel

computeSelfCost

public PlanCost computeSelfCost(SaffronPlanner planner)

Description copied from class: SaffronRel

Returns the cost of this plan (not including children). The base implementation throws an error; derived classes should override.

Overrides:

computeSelfCost in class SaffronRel

deriveRowType

protected SaffronType deriveRowType()

Overrides:

deriveRowType in class SingleRel