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Hadoop >> mail # user >> only ouput values, no keys, no reduce


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huanchen.zhang 2012-06-11, 13:10
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Re: only ouput values, no keys, no reduce
You can use Hadoop NullWritable

http://hadoop.apache.org/common/docs/r1.0.1/api/org/apache/hadoop/io/NullWritable.Comparator.html

Mark

On Mon, Jun 11, 2012 at 8:10 AM, huanchen.zhang
<[EMAIL PROTECTED]>wrote:

> hi,
>
> I am developing a map reduce program which has no reduce. And I just want
> the maps to output all the values which meet some requrements (no keys
> output).
>
> what should I do in this case? I tried context.write(Text, Text), but it
> outputs both keys and values.
>
> Thank you !
>
> Best,
> Huanchen
>
> 2012-06-11
>
>
>
> huanchen.zhang
>
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顾晟 2012-06-12, 10:42
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