org.apache.beam.sdk.extensions.sql.impl.planner

Class NodeStats

java.lang.Object

org.apache.beam.sdk.extensions.sql.impl.planner.NodeStats

public abstract class NodeStats
extends java.lang.Object

This is a utility class to represent rowCount, rate and window.

Field Summary

Fields

Modifier and Type	Field and Description
static NodeStats	UNKNOWN Returns an instance with all values set to INFINITY.

Constructor Summary

Constructors

Constructor and Description
NodeStats()

Method Summary

Modifier and Type	Method and Description
static NodeStats	create(double rowCount) It creates an instance with rate=0 and window=rowCount for bounded sources.
static NodeStats	create(double rowCount, double rate, double window)
abstract double	getRate()
abstract double	getRowCount()
abstract double	getWindow() This method returns the number of tuples in each window.
boolean	isUnknown() If any of the values for rowCount, rate or window is infinite, it returns true.
NodeStats	minus(NodeStats that)
NodeStats	multiply(double factor)
NodeStats	plus(NodeStats that)

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN

public static final NodeStats UNKNOWN

Returns an instance with all values set to INFINITY. This will be only used when the node is not a BeamRelNode and we don't have an estimation implementation for it in the metadata handler. In this case we return INFINITE and it will be propagated up in the estimates.

Constructor Detail

NodeStats

public NodeStats()

Method Detail

getRowCount

public abstract double getRowCount()

getRate

public abstract double getRate()

getWindow

public abstract double getWindow()

This method returns the number of tuples in each window. It is different than the windowing notion of Beam.

create

public static NodeStats create(double rowCount,
                               double rate,
                               double window)

create

public static NodeStats create(double rowCount)

It creates an instance with rate=0 and window=rowCount for bounded sources.

isUnknown

public boolean isUnknown()

If any of the values for rowCount, rate or window is infinite, it returns true.

multiply

public NodeStats multiply(double factor)

plus

public NodeStats plus(NodeStats that)

minus

public NodeStats minus(NodeStats that)