Package org.apache.druid.query.aggregation.last

Class StringLastFoldingAggregatorFactory

java.lang.Object

org.apache.druid.query.aggregation.AggregatorFactory

org.apache.druid.query.aggregation.last.StringLastAggregatorFactory

org.apache.druid.query.aggregation.last.StringLastFoldingAggregatorFactory

All Implemented Interfaces:

Cacheable

public class StringLastFoldingAggregatorFactory
extends StringLastAggregatorFactory

For backwards compatibility; equivalent to a regular StringLastAggregatorFactory.

Field Summary

Fields inherited from class org.apache.druid.query.aggregation.last.StringLastAggregatorFactory

maxStringBytes, TYPE

Constructor Summary

Constructors

Constructor	Description
StringLastFoldingAggregatorFactory(String name, String fieldName, Integer maxStringBytes)

Method Summary

Modifier and Type	Method	Description
AggregatorFactory	withName(String newName)	Used in cases where we want to change the output name of the aggregator to something else.

Methods inherited from class org.apache.druid.query.aggregation.last.StringLastAggregatorFactory

canVectorize, combine, deserialize, equals, factorize, factorizeBuffered, factorizeVector, finalizeComputation, getCacheKey, getCombiningFactory, getComparator, getFieldName, getIntermediateType, getMaxIntermediateSize, getMaxStringBytes, getName, getResultType, getTimeColumn, hashCode, makeAggregateCombiner, requiredFields, toString

Methods inherited from class org.apache.druid.query.aggregation.AggregatorFactory

factorizeWithSize, getComplexTypeName, getFinalizedType, getMaxIntermediateSizeWithNulls, getMergingFactory, getRequiredColumns, getType, guessAggregatorHeapFootprint, makeNullableAggregateCombiner, mergeAggregators, optimizeForSegment

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

StringLastFoldingAggregatorFactory

public StringLastFoldingAggregatorFactory(String name,
                                          String fieldName,
                                          Integer maxStringBytes)

Method Detail

withName

public AggregatorFactory withName(String newName)

Description copied from class: AggregatorFactory

Used in cases where we want to change the output name of the aggregator to something else. For eg: if we have a query `select a, sum(b) as total group by a from table` the aggregator returned from the native group by query is "a0" set in org.apache.druid.sql.calcite.rel.DruidQuery#computeAggregations. We can use withName("total") to set the output name of the aggregator to "total".

As all implementations of this interface method may not exist, callers of this method are advised to handle such a case.

Overrides:

withName in class StringLastAggregatorFactory

Parameters:

newName - newName of the output for aggregator factory

Returns:

AggregatorFactory with the output name set as the input param.