Package org.apache.flink.table.plan.stats

Class ColumnStats

java.lang.Object

org.apache.flink.table.plan.stats.ColumnStats

@PublicEvolving
public final class ColumnStats
extends Object

Column statistics.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ColumnStats.Builder	ColumnStats builder.

Field Summary

Fields

Modifier and Type	Field	Description
static ColumnStats	UNKNOWN	Unknown definition for column stats.

Constructor Summary

Constructors

Constructor	Description
ColumnStats(Long ndv, Long nullCount, Double avgLen, Integer maxLen, Comparable<?> max, Comparable<?> min)

Method Summary

Modifier and Type	Method	Description
ColumnStats	copy()	Create a deep copy of "this" instance.
boolean	equals(Object o)
Double	getAvgLen()
Comparable<?>	getMax()
Integer	getMaxLen()
Comparable<?>	getMin()
Long	getNdv()
Long	getNullCount()
int	hashCode()
ColumnStats	merge(ColumnStats other, boolean isPartitionKey)	Merges two column stats.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN

public static final ColumnStats UNKNOWN

Unknown definition for column stats.

Constructor Detail

ColumnStats

public ColumnStats(Long ndv,
                   Long nullCount,
                   Double avgLen,
                   Integer maxLen,
                   Comparable<?> max,
                   Comparable<?> min)

Method Detail

getNdv

public Long getNdv()

getNullCount

public Long getNullCount()

getAvgLen

public Double getAvgLen()

getMaxLen

public Integer getMaxLen()

getMax

public Comparable<?> getMax()

getMin

public Comparable<?> getMin()

toString

public String toString()

Overrides:

toString in class Object

copy

public ColumnStats copy()

Create a deep copy of "this" instance.

Returns:

a deep copy

merge

public ColumnStats merge(ColumnStats other,
                         boolean isPartitionKey)

Merges two column stats. When the stats are unknown, whatever the other are, we need return unknown stats. The unknown definition for column stats is null.

Parameters:

other - The other column stats to merge.

Returns:

The merged column stats.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object