org.apache.calcite.adapter.pig

Class PigAggregate

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.SingleRel

org.apache.calcite.rel.core.Aggregate

org.apache.calcite.adapter.pig.PigAggregate

All Implemented Interfaces:

Cloneable, PigRel, RelOptNode, RelNode

public class PigAggregate
extends Aggregate
implements PigRel

Implementation of Aggregate in Pig calling convention.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.calcite.rel.core.Aggregate

Aggregate.AggCallBinding, Aggregate.Group

Nested classes/interfaces inherited from interface org.apache.calcite.adapter.pig.PigRel

PigRel.Implementor

Nested classes/interfaces inherited from interface org.apache.calcite.rel.RelNode

RelNode.Context

Field Summary

Fields

Modifier and Type	Field and Description
static String	DISTINCT_FIELD_SUFFIX

Fields inherited from class org.apache.calcite.rel.core.Aggregate

aggCalls, groupSet, groupSets, indicator, IS_NOT_GRAND_TOTAL, IS_SIMPLE, NO_INDICATOR

Fields inherited from class org.apache.calcite.rel.SingleRel

input

Fields inherited from class org.apache.calcite.rel.AbstractRelNode

digest, id, rowType, traitSet

Fields inherited from interface org.apache.calcite.adapter.pig.PigRel

CONVENTION

Constructor Summary

Constructors

Constructor and Description
PigAggregate(RelOptCluster cluster, RelTraitSet traits, RelNode child, boolean indicator, ImmutableBitSet groupSet, List<ImmutableBitSet> groupSets, List<AggregateCall> aggCalls) Creates a PigAggregate.

Method Summary

Modifier and Type	Method and Description
Aggregate	copy(RelTraitSet traitSet, RelNode input, boolean indicator, ImmutableBitSet groupSet, List<ImmutableBitSet> groupSets, List<AggregateCall> aggCalls)
private List<String>	getArgNames(String relAlias, AggregateCall aggCall)
private List<String>	getDistinctCalls(PigRel.Implementor implementor) A agg function call like COUNT(DISTINCT COL) in Pig is achieved via two statements in a FOREACH that follows a GROUP statement: TABLE = GROUP TABLE ALL; TABLE = FOREACH TABLE { COL.DISTINCT = DISTINCT COL; GENERATE COUNT(COL.DISTINCT) AS C; }
private String	getInputFieldName(int fieldIndex)
private String	getInputFieldNameForAggCall(String relAlias, AggregateCall aggCall, int fieldIndex)
private String	getPigAggregateCall(String relAlias, AggregateCall aggCall)
private List<String>	getPigAggregateCalls(PigRel.Implementor implementor)
private String	getPigAggregateStatement(PigRel.Implementor implementor) Generates a GROUP BY statement, followed by an optional FOREACH statement for all aggregate functions used.
private String	getPigForEachGenerate(PigRel.Implementor implementor) Generates a FOREACH statement containing invocation of aggregate functions and projection of grouped fields.
private String	getPigGenerateCall(PigRel.Implementor implementor)
private String	getPigGroupBy(PigRel.Implementor implementor) Generates the GROUP BY statement, e.g.
RelOptTable	getTable() Override this method so it looks down the tree to find the table this node is acting on.
void	implement(PigRel.Implementor implementor) Converts this node to a Pig Latin statement.
private PigAggFunction	toPigAggFunc(AggregateCall aggCall)

Methods inherited from class org.apache.calcite.rel.core.Aggregate

computeSelfCost, containsDistinctCall, copy, deriveRowType, deriveRowType, estimateRowCount, explainTerms, getAggCallList, getGroupCount, getGroupSet, getGroupSets, getGroupType, getIndicatorCount, getNamedAggCalls, isValid

Methods inherited from class org.apache.calcite.rel.SingleRel

childrenAccept, getInput, getInputs, replaceInput

Methods inherited from class org.apache.calcite.rel.AbstractRelNode

accept, accept, collectVariablesSet, collectVariablesUsed, computeDigest, computeSelfCost, explain, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getQuery, getRelTypeName, getRows, getRowType, getTraitSet, getVariablesSet, getVariablesStopped, isDistinct, isKey, isValid, metadata, onRegister, recomputeDigest, register, sole, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.calcite.rel.RelNode

accept, accept, childrenAccept, collectVariablesSet, collectVariablesUsed, computeSelfCost, computeSelfCost, copy, estimateRowCount, explain, getChildExps, getCollationList, getConvention, getCorrelVariable, getExpectedInputRowType, getInput, getInputs, getQuery, getRelTypeName, getRows, getRowType, getVariablesSet, getVariablesStopped, isDistinct, isKey, isValid, isValid, metadata, onRegister, recomputeDigest, register, replaceInput

Methods inherited from interface org.apache.calcite.plan.RelOptNode

getCluster, getDescription, getDigest, getId, getTraitSet

Field Detail

DISTINCT_FIELD_SUFFIX

public static final String DISTINCT_FIELD_SUFFIX

See Also:

Constant Field Values

Constructor Detail

PigAggregate

public PigAggregate(RelOptCluster cluster,
                    RelTraitSet traits,
                    RelNode child,
                    boolean indicator,
                    ImmutableBitSet groupSet,
                    List<ImmutableBitSet> groupSets,
                    List<AggregateCall> aggCalls)

Creates a PigAggregate.

Method Detail

copy

public Aggregate copy(RelTraitSet traitSet,
                      RelNode input,
                      boolean indicator,
                      ImmutableBitSet groupSet,
                      List<ImmutableBitSet> groupSets,
                      List<AggregateCall> aggCalls)

Specified by:

copy in class Aggregate

implement

public void implement(PigRel.Implementor implementor)

Description copied from interface: PigRel

Converts this node to a Pig Latin statement.

Specified by:

implement in interface PigRel

getPigAggregateStatement

private String getPigAggregateStatement(PigRel.Implementor implementor)

Generates a GROUP BY statement, followed by an optional FOREACH statement for all aggregate functions used. e.g.

 
 A = GROUP A BY owner;
 A = FOREACH A GENERATE group, SUM(A.pet_num);
 
 

getTable

public RelOptTable getTable()

Override this method so it looks down the tree to find the table this node is acting on.

Specified by:

getTable in interface RelNode

Overrides:

getTable in class AbstractRelNode

getPigGroupBy

private String getPigGroupBy(PigRel.Implementor implementor)

Generates the GROUP BY statement, e.g. A = GROUP A BY (f1, f2);

getPigForEachGenerate

private String getPigForEachGenerate(PigRel.Implementor implementor)

Generates a FOREACH statement containing invocation of aggregate functions and projection of grouped fields. e.g. A = FOREACH A GENERATE group, SUM(A.pet_num);

See Also:

documentation for special meaning of the "group" field after GROUP BY.

getPigGenerateCall

private String getPigGenerateCall(PigRel.Implementor implementor)

getPigAggregateCalls

private List<String> getPigAggregateCalls(PigRel.Implementor implementor)

getPigAggregateCall

private String getPigAggregateCall(String relAlias,
                                   AggregateCall aggCall)

toPigAggFunc

private PigAggFunction toPigAggFunc(AggregateCall aggCall)

getArgNames

private List<String> getArgNames(String relAlias,
                                 AggregateCall aggCall)

getInputFieldNameForAggCall

private String getInputFieldNameForAggCall(String relAlias,
                                           AggregateCall aggCall,
                                           int fieldIndex)

getDistinctCalls

private List<String> getDistinctCalls(PigRel.Implementor implementor)

A agg function call like COUNT(DISTINCT COL) in Pig is achieved via two statements in a FOREACH that follows a GROUP statement:

TABLE = GROUP TABLE ALL;
TABLE = FOREACH TABLE {
COL.DISTINCT = DISTINCT COL;
GENERATE COUNT(COL.DISTINCT) AS C;
}

getInputFieldName

private String getInputFieldName(int fieldIndex)