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Pig >> mail # dev >> Sampling in operations like Order by


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Re: Sampling in operations like Order by
The first job simply read input and dump to hdfs. The need for first job is:
1. SampleLoader does not work with non-hdfs loader
2. SampleLoader does not process any operators before "order by"

In some cases the first job can be optimized out, see
org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.SampleOptimizer

Thanks,
Daniel

On Thu, May 22, 2014 at 8:04 PM, Ruoyu Liu <[EMAIL PROTECTED]> wrote:

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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