Module datarush.library

Package com.pervasive.datarush.ports.record

Class DynamicRangeDataDistribution

java.lang.Object

com.pervasive.datarush.ports.record.DataDistribution

com.pervasive.datarush.ports.record.PartialDataDistribution

com.pervasive.datarush.ports.record.PartialDynamicDataDistribution

com.pervasive.datarush.ports.record.DynamicRangeDataDistribution

public final class DynamicRangeDataDistribution
extends PartialDynamicDataDistribution

A distribution where data is range-partitioned by a selected array of keys. Ranges are dynamically computed so as to find split points that guarantee that the data is roughly evenly distributed. Data is sampled and the split points are set to evenly-spaces quantiles within the sample.

See Also:

DataDistribution

Constructor Summary

Constructors

Constructor	Description
DynamicRangeDataDistribution(String... keys)	Creates a range distribution for a list of range keys.
DynamicRangeDataDistribution(List<String> keys)	Creates a range distribution for a list of range keys.

Method Summary

Modifier and Type	Method	Description
AliasSet[]	getAliases()	Returns the fields that are referenced by this distribution.
String[]	getKeys()	Returns the keys by which we are range-partitioned.
boolean	isGroupedBy(String[] keys)	Returns true if this range distribution exactly matches the specified list of keys.
PartialDataDistribution	remap(FieldRemapping mapping)	Applies the given field remapping to this mapping, changing names as required.
String	toString()

Methods inherited from class com.pervasive.datarush.ports.record.PartialDataDistribution

getGatherScheme

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicRangeDataDistribution

public DynamicRangeDataDistribution(List<String> keys)

Creates a range distribution for a list of range keys.

Parameters:

keys - the range keys

DynamicRangeDataDistribution

public DynamicRangeDataDistribution(String... keys)

Creates a range distribution for a list of range keys.

Parameters:

keys - the range keys

Method Detail

isGroupedBy

public boolean isGroupedBy(String[] keys)

Returns true if this range distribution exactly matches the specified list of keys.

Parameters:

keys - the range keys

Returns:

whether this distribution exactly matches the specified list of keys

toString

public String toString()

Specified by:

toString in class DataDistribution

getKeys

public String[] getKeys()

Returns the keys by which we are range-partitioned.

Returns:

the keys by which we are range-partitioned.

remap

public PartialDataDistribution remap(FieldRemapping mapping)

Applies the given field remapping to this mapping, changing names as required. If any range keys refer to columns that are dropped as part of the rename, the result is an UnspecifiedPartialDistribution.

Specified by:

remap in class DataDistribution

Parameters:

mapping - the field remapping.

Returns:

this distribution, remapped to the new names.

getAliases

public AliasSet[] getAliases()

Description copied from class: DataDistribution

Returns the fields that are referenced by this distribution. Note that it is valid for a distribution to reference no fields, in which case it should return an empty array. This method is used by the framework to validate the distribution is consistent with the type of the record.

Specified by:

getAliases in class DataDistribution

Returns:

the fields that are referenced by this distribution