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Hive >> mail # user >> Map-only aggregation


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Map-only aggregation
Hi all,

Can Hive implement the aggregation as a Map-only job? As we know the
data may be pre-partitioned via PARTITION-BY or CLUSTERED-BY, so we
don't need the reduce phase to repartition the data.

The Bucket Join seems to take advantage of the buckets for joins, so I
wonder if there is some similar optimization for aggregations.

Thanks,
Jie
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB