mapreduce reduce排序-阿里云

MapReduce的reduce中Iterable<Text> value中数据的排序规则

请求在MR程序中，reduce阶段，reduce方法reduce(Text key, Iterable value,Reducer.Context context)，同一个key的velue迭代器列表中value的排序规则，是根据字符串的hash排序吗？

编写MapReduce作业时，如何做到在Reduce阶段，先对key排序，再对value排序？

Hadoop 分布式计算框架 MapReduce

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在编写MapReduce时，在Reduce阶段，如何做到先对key排序，再对value排序？

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更新时间 2024-03-12 12:58:13

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开源大数据平台 E-MapReduce

开源大数据平台 E-MapReduce（简称“EMR”）是云原生开源大数据平台，向客户提供简单易集成的Hadoop、Hive、Spark、Flink、Presto、ClickHouse、StarRocks、Delta、Hudi等开源大数据计算和存储引擎服务。

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