ToKeyGroup(Object key, int maxParallelism) { Preconditions.checkNotNull(key, "Assigned key must not be null!"); return computeKeyGroupForKeyHash(key.hashCode(), maxParallelism); } //2.使用murmurHash进行计算,并和最大并行度进行求余运算 public static int computeKeyGroupForKeyHash(int keyHash,...
key=keySelector.getKey(record.getInstance().getValue()); }catch(Exceptione) { thrownewRuntimeException( "Could not extract key from "+record.getInstance().getValue(),e); } returnKeyGroupRangeAssignment.assignKeyToParallelOperator( key,maxParallelism,numberOfChannels); } 1. 2. 3. 4. 5. ...
// key为分组键,maxParallelism由系统定义默认128,numberOfChannels为用户定义并行度@OverridepublicintselectChannel(SerializationDelegate<StreamRecord<T>>record){Kkey;try{key=keySelector.getKey(record.getInstance().getValue());}catch(Exceptione){thrownewRuntimeException("Could not extract key from "+reco...
@OverridepublicintselectChannel(SerializationDelegate<StreamRecord<T>>record){K key;try{key=keySelector.getKey(record.getInstance().getValue());}catch(Exception e){thrownewRuntimeException("Could not extract key from "+record.getInstance().getValue(),e);}/** * key:按什么分组的值 * maxParal...
().getValue());}catch(Exceptione){thrownewRuntimeException("Could not extract key from "+record.getInstance().getValue(),e);}//调用KeyGroupRangeAssignment类的assignKeyToParallelOperator方法,代码如下所示returnKeyGroupRangeAssignment.assignKeyToParallelOperator(key,maxParallelism,numberOfChannels);}.....
EPOCH, EQUALS, ESCAPE, EVERY, EXCEPT, EXCEPTION, EXCLUDE, EXCLUDING, EXEC, EXECUTE, EXISTS, EXP, EXPLAIN, EXTEND, EXTERNAL, EXTRACT, FALSE, FETCH, FILTER, FINAL, FIRST, FIRST_VALUE, FLOAT, FLOOR, FOLLOWING, FOR, FOREIGN, FORTRAN, FOUND, FRAC_SECOND, FREE, FROM, FULL, FUNCTION, FUSION, ...
例如上游kafka发送的时候指定的key出现了数据热点问题,那么就在接入之后,做一个负载均衡(前提下游不是keyby)。 聚合类算子数据倾斜 预聚合加全局聚合 12、flink 维表关联怎么做的 1.async io 2.broadcast 3.async io + cache 4.open方法中读取,然后定时线程刷新,缓存更新是先删除,之后再来一条之后再负责写入缓存...
input.getKeyType()); }// KeyedStream类型,表示被加窗的输入流。privatefinalKeyedStream<T, K> input;// 用于构建WindowOperator,最终会生成windowAssigner,Evictor,TriggerprivatefinalWindowOperatorBuilder<T, K, W> builder; 在这里面还涉及到一些窗口的基本计算算子,比如reduce,aggregate,apply,process,sum等等...
`ts` TIMESTAMP_LTZ(3) METADATA FROM 'timestamp' VIRTUAL, ... ) WITH ( 'connector' = 'kafka', ... ); The following table describes the metadata columns supported by Kafka source tables and sink tables. Key Data type Description Source table or sink table topic STRING NOT NULL METADATA...
Key Data type Description Source table or result table topic STRING NOT NULL METADATA VIRTUAL The name of the topic to which the Kafka message belongs. Source table partition INT NOT NULL METADATA VIRTUAL The ID of the partition to which the Kafka message belongs. Source table headers MAP<...