com.yahoo.bullet.querying.aggregations

Class TupleSketchingStrategy

java.lang.Object

com.yahoo.bullet.querying.aggregations.SketchingStrategy<S>

com.yahoo.bullet.querying.aggregations.TupleSketchingStrategy

All Implemented Interfaces:

Closable, Monoidal, Strategy

public class TupleSketchingStrategy
extends SketchingStrategy<S>

This Strategy implements a Tuple Sketch based approach to doing a group by. In particular, it provides a uniform sample of the groups if the number of unique groups exceed the Sketch size. Metrics like sum and count when summed across the uniform sample and divided the sketch theta gives an approximate estimate of the total sum and count across all the groups.

Field Summary

Fields inherited from class com.yahoo.bullet.querying.aggregations.SketchingStrategy

fields, metadataKeys, separator, sketch

Constructor Summary

Constructors

Constructor and Description
TupleSketchingStrategy(GroupBy aggregation, BulletConfig config) Constructor that requires an Aggregation and a BulletConfig configuration.

Method Summary

Modifier and Type	Method and Description
void	consume(com.yahoo.bullet.record.BulletRecord data) Consumes a single BulletRecord into this Monoid.
static com.yahoo.sketches.ResizeFactor	getResizeFactor(int factor) Converts a integer representing the resizing for Sketches into a ResizeFactor.

Methods inherited from class com.yahoo.bullet.querying.aggregations.SketchingStrategy

combine, getData, getMetadata, getRecords, getResult, reset

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.yahoo.bullet.querying.aggregations.Strategy

isClosed

Methods inherited from interface com.yahoo.bullet.common.Monoidal

merge

Constructor Detail

TupleSketchingStrategy

public TupleSketchingStrategy(GroupBy aggregation,
                              BulletConfig config)

Constructor that requires an Aggregation and a BulletConfig configuration.

Parameters:

aggregation - An Aggregation with valid fields and attributes for this aggregation type.

config - The config that has relevant configs for this strategy.

Method Detail

consume

public void consume(com.yahoo.bullet.record.BulletRecord data)

Description copied from interface: Monoidal

Consumes a single BulletRecord into this Monoid.

Parameters:

data - The BulletRecord to consume.

getResizeFactor

public static com.yahoo.sketches.ResizeFactor getResizeFactor(int factor)

Converts a integer representing the resizing for Sketches into a ResizeFactor.

Parameters:

factor - An int representing the scaling when the Sketch reaches its threshold. Supports 1, 2, 4 and 8.

Returns:

A ResizeFactor represented by the integer or ResizeFactor.X8 otherwise.