org.apache.druid.query.aggregation.cardinality.types

Class DoubleCardinalityAggregatorColumnSelectorStrategy

java.lang.Object

org.apache.druid.query.aggregation.cardinality.types.DoubleCardinalityAggregatorColumnSelectorStrategy

All Implemented Interfaces:

CardinalityAggregatorColumnSelectorStrategy<BaseDoubleColumnValueSelector>, ColumnSelectorStrategy

public class DoubleCardinalityAggregatorColumnSelectorStrategy
extends Object
implements CardinalityAggregatorColumnSelectorStrategy<BaseDoubleColumnValueSelector>

If performance of this class appears to be a bottleneck for somebody, one simple way to improve it is to split it into two different classes, one that is used when NullHandling.replaceWithDefault() is false, and one - when it's true, moving this computation out of the tight loop

Constructor Summary

Constructors

Constructor and Description
DoubleCardinalityAggregatorColumnSelectorStrategy()

Method Summary

Modifier and Type	Method and Description
void	hashRow(BaseDoubleColumnValueSelector selector, com.google.common.hash.Hasher hasher) Retrieve the current row from dimSelector and add the row values to the hasher.
void	hashValues(BaseDoubleColumnValueSelector selector, HyperLogLogCollector collector) Retrieve the current row from dimSelector and add the row values to HyperLogLogCollector.

Methods inherited from class java.lang.Object

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

Constructor Detail

DoubleCardinalityAggregatorColumnSelectorStrategy

public DoubleCardinalityAggregatorColumnSelectorStrategy()

Method Detail

hashRow

public void hashRow(BaseDoubleColumnValueSelector selector,
                    com.google.common.hash.Hasher hasher)

Description copied from interface: CardinalityAggregatorColumnSelectorStrategy

Retrieve the current row from dimSelector and add the row values to the hasher.

Specified by:

hashRow in interface CardinalityAggregatorColumnSelectorStrategy<BaseDoubleColumnValueSelector>

Parameters:

selector - Dimension value selector

hasher - Hasher used for cardinality aggregator calculations

hashValues

public void hashValues(BaseDoubleColumnValueSelector selector,
                       HyperLogLogCollector collector)

Description copied from interface: CardinalityAggregatorColumnSelectorStrategy

Retrieve the current row from dimSelector and add the row values to HyperLogLogCollector.

Specified by:

hashValues in interface CardinalityAggregatorColumnSelectorStrategy<BaseDoubleColumnValueSelector>

Parameters:

selector - Dimension value selector

collector - HLL collector used for cardinality aggregator calculations