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From Harsh J <ha...@cloudera.com>
Subject Re: Hadoop Avro Question
Date Wed, 01 May 2013 05:06:15 GMT
Oops, moving for sure this time :)

On Wed, May 1, 2013 at 10:35 AM, Harsh J <harsh@cloudera.com> wrote:
> Moving the question to Apache Avro's user@ lists. Please use the right
> lists for the most relevant answers.
>
> Avro is a different serialization technique that intends to replace
> the Writable serialization defaults in Hadoop. MR accepts a list of
> serializers it can use for its key/value structures and isn't limited
> to Writable in any way. Look up the property "io.serializations" in
> your Hadoop's core-default.xml for more information.
>
> The Avro project also offers fast comparator classes that are used for
> comparing the bytes/structures of Avro objects. This is mostly
> auto-set for you when you use the MR framework as described at
> http://avro.apache.org/docs/current/api/java/org/apache/avro/mapred/package-summary.html
> (via AvroJob helper class).
>
> On Tue, Apr 30, 2013 at 6:51 PM, Rahul Bhattacharjee
> <rahul.rec.dgp@gmail.com> wrote:
>> Hi,
>>
>> When dealing with Avro data files in MR jobs ,we use AvroMapper , I noticed
>> that the output of K and V of AvroMapper isnt writable and neither the key
>> is comparable (these are AvroKey and AvroValue). As the general
>> serialization mechanism is writable , how is the K,V pairs in case of avro ,
>> travel across nodes?
>>
>> Thanks,
>> Rahul
>
>
>
> --
> Harsh J



-- 
Harsh J

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