Hive实现原理-阿里云

Hive Distinct 的实现原理

Hive Distinct 的实现原理select dealid, count(distinct uid) num from order group by dealid;当只有一个distinct字段时，如果不考虑Map阶段的Hash GroupBy，只需要将GroupBy字段和Distinct字段...

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Hive mapreduce SQL实现原理——SQL最终分解为MR任务，而group by在MR里和单词统计MR没有区别了

转自：http://blog.csdn.net/sn_zzy/article/details/43446027 SQL转化为MapReduce的过程了解了MapReduce实现SQL基本操作之后，我们来看看Hive是如何将SQL转化为MapReduce任务的，整个编译过程分为六个阶段： Antlr...

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更新时间 2024-02-20 12:21:05

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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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