org.apache.iceberg.flink.sink.shuffle.DataStatistics Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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*/
package org.apache.iceberg.flink.sink.shuffle;
import org.apache.flink.annotation.Internal;
import org.apache.iceberg.SortKey;
/**
* DataStatistics defines the interface to collect data distribution information.
*
* Data statistics tracks traffic volume distribution across data keys. For low-cardinality key,
* a simple map of (key, count) can be used. For high-cardinality key, probabilistic data structures
* (sketching) can be used.
*/
@Internal
interface DataStatistics, S> {
/**
* Check if data statistics contains any statistics information.
*
* @return true if data statistics doesn't contain any statistics information
*/
boolean isEmpty();
/** Add row sortKey to data statistics. */
void add(SortKey sortKey);
/**
* Merge current statistics with other statistics.
*
* @param otherStatistics the statistics to be merged
*/
void merge(D otherStatistics);
/**
* Get the underline statistics.
*
* @return the underline statistics
*/
S statistics();
}