org.apache.paimon.mergetree.compact

Interface MergeFunction<T>

Type Parameters:

T - result type

All Known Implementing Classes:

AggregateMergeFunction, DeduplicateMergeFunction, FirstRowMergeFunction, LookupMergeFunction, PartialUpdateMergeFunction

public interface MergeFunction<T>

Merge function to merge multiple KeyValues.

IMPORTANT, Object reusing inside the kv of the add(org.apache.paimon.KeyValue) input:

• Please don't save KeyValue and InternalRow references to the List: the KeyValue of the first two objects and the InternalRow object inside them are safe, but the reference of the third object may overwrite the reference of the first object.
• You can save fields references: fields don't reuse their objects.

Method Summary

Modifier and Type	Method and Description
void	add(KeyValue kv) Add the given KeyValue to the merge function.
T	getResult() Get current merged value.
boolean	requireCopy()
void	reset() Reset the merge function to its default state, call this before calling add(KeyValue) for the first time or after getResult().

Method Detail

reset

void reset()

Reset the merge function to its default state, call this before calling add(KeyValue) for the first time or after getResult().

add

void add(KeyValue kv)

Add the given KeyValue to the merge function.

getResult

T getResult()

Get current merged value.

requireCopy

boolean requireCopy()