org.apache.flink.table.runtime.operators.rank

Class UpdatableTopNFunction

java.lang.Object

org.apache.flink.api.common.functions.AbstractRichFunction

org.apache.flink.streaming.api.functions.KeyedProcessFunction<org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData>

org.apache.flink.table.runtime.operators.rank.AbstractTopNFunction

org.apache.flink.table.runtime.operators.rank.UpdatableTopNFunction

All Implemented Interfaces:

Serializable, org.apache.flink.api.common.functions.Function, org.apache.flink.api.common.functions.RichFunction, org.apache.flink.streaming.api.checkpoint.CheckpointedFunction

public class UpdatableTopNFunction
extends AbstractTopNFunction
implements org.apache.flink.streaming.api.checkpoint.CheckpointedFunction

A TopN function could handle updating stream. It is a fast version of RetractableTopNFunction which only hold top n data in state, and keep sorted map in heap. However, the function only works in some special scenarios: 1. sort field collation is ascending and its mono is decreasing, or sort field collation is descending and its mono is increasing 2. input data has unique keys and unique key must contain partition key 3. input stream could not contain DELETE record or UPDATE_BEFORE record

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.streaming.api.functions.KeyedProcessFunction

org.apache.flink.streaming.api.functions.KeyedProcessFunction.Context, org.apache.flink.streaming.api.functions.KeyedProcessFunction.OnTimerContext

Field Summary

Fields inherited from class org.apache.flink.table.runtime.operators.rank.AbstractTopNFunction

hitCount, inputRowType, keyContext, outputRankNumber, rankEnd, requestCount, sortKeyComparator, sortKeySelector, ttlConfig

Constructor Summary

Constructors

Constructor and Description
UpdatableTopNFunction(org.apache.flink.api.common.state.StateTtlConfig ttlConfig, InternalTypeInfo<org.apache.flink.table.data.RowData> inputRowType, RowDataKeySelector rowKeySelector, GeneratedRecordComparator generatedRecordComparator, RowDataKeySelector sortKeySelector, RankType rankType, RankRange rankRange, boolean generateUpdateBefore, boolean outputRankNumber, long cacheSize)

Method Summary

Modifier and Type	Method and Description
void	initializeState(org.apache.flink.runtime.state.FunctionInitializationContext context)
void	open(org.apache.flink.api.common.functions.OpenContext openContext)
void	processElement(org.apache.flink.table.data.RowData input, org.apache.flink.streaming.api.functions.KeyedProcessFunction.Context context, org.apache.flink.util.Collector<org.apache.flink.table.data.RowData> out)
void	snapshotState(org.apache.flink.runtime.state.FunctionSnapshotContext context)

Methods inherited from class org.apache.flink.table.runtime.operators.rank.AbstractTopNFunction

checkSortKeyInBufferRange, collectDelete, collectDelete, collectInsert, collectInsert, collectUpdateAfter, collectUpdateAfter, collectUpdateBefore, collectUpdateBefore, getDefaultTopNSize, hasOffset, initRankEnd, isInRankEnd, isInRankRange, registerMetric, setKeyContext

Methods inherited from class org.apache.flink.streaming.api.functions.KeyedProcessFunction

onTimer

Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

close, getIterationRuntimeContext, getRuntimeContext, open, setRuntimeContext

Methods inherited from class java.lang.Object

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

Constructor Detail

UpdatableTopNFunction

public UpdatableTopNFunction(org.apache.flink.api.common.state.StateTtlConfig ttlConfig,
                             InternalTypeInfo<org.apache.flink.table.data.RowData> inputRowType,
                             RowDataKeySelector rowKeySelector,
                             GeneratedRecordComparator generatedRecordComparator,
                             RowDataKeySelector sortKeySelector,
                             RankType rankType,
                             RankRange rankRange,
                             boolean generateUpdateBefore,
                             boolean outputRankNumber,
                             long cacheSize)

Method Detail

open

public void open(org.apache.flink.api.common.functions.OpenContext openContext)
          throws Exception

Specified by:

open in interface org.apache.flink.api.common.functions.RichFunction

Overrides:

open in class AbstractTopNFunction

Throws:

Exception

initializeState

public void initializeState(org.apache.flink.runtime.state.FunctionInitializationContext context)
                     throws Exception

Specified by:

initializeState in interface org.apache.flink.streaming.api.checkpoint.CheckpointedFunction

Throws:

Exception

processElement

public void processElement(org.apache.flink.table.data.RowData input,
                           org.apache.flink.streaming.api.functions.KeyedProcessFunction.Context context,
                           org.apache.flink.util.Collector<org.apache.flink.table.data.RowData> out)
                    throws Exception

Specified by:

processElement in class org.apache.flink.streaming.api.functions.KeyedProcessFunction<org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData>

Throws:

Exception

snapshotState

public void snapshotState(org.apache.flink.runtime.state.FunctionSnapshotContext context)
                   throws Exception

Specified by:

snapshotState in interface org.apache.flink.streaming.api.checkpoint.CheckpointedFunction

Throws:

Exception