All right, thanks~
2012/9/17 feng lu <amuseme.lu@gmail.com>
> Hi
> Maybe you can refer to
>
> http://hadoop.apache.org/docs/r1.0.3/api/org/apache/hadoop/mapred/lib/MultipleSequenceFileOutputFormat.html
>
> or
>
>
> http://hadoop.apache.org/docs/r1.0.3/api/org/apache/hadoop/mapred/lib/MultipleTextOutputFormat.html
>
> example like this
>
> public static class GeneratorOutputFormat extends
> MultipleSequenceFileOutputFormat<IntWritable,Text> {
> // generate a filename based on the segnum stored for this text
> protected String generateFileNameForKeyValue(IntWritable key, Text
> value,
> String name) {
> return "ID_" + key.get() + ".dat";
> }
>
> }
>
> On Mon, Sep 17, 2012 at 3:16 PM, Jason Yang <lin.yang.jason@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering how to write all the input with the same key to a single
>> file in the reducer ?
>>
>> say, I got some intermediate outputs from mappers like that:
>> key value
>> --------------------
>> 1 annie
>> 2 Jason
>> 1 andy
>> 2 Joey
>> 1 andrew
>> ...
>>
>> and I would like write all the intermediate outputs with key 1 to file
>> "ID_1.dat", and all the intermediate outputs with key 2 to file "ID_2.data".
>>
>> how could I achieve that?
>>
>> --
>> YANG, Lin
>>
>>
>
>
> --
> Don't Grow Old, Grow Up... :-)
>
--
YANG, Lin
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