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From Roth Effy <effyr...@gmail.com>
Subject Re: How can I record some position of context in Reduce()?
Date Wed, 13 Mar 2013 02:50:35 GMT
I want to join two table data in reducer.So I need to find the start of the
table.
someone said the DataJoinReducerBase can help me,isn't it?


2013/3/13 Azuryy Yu <azuryyyu@gmail.com>

> you cannot use RecordReader in Reducer.
>
> what's the mean of you want get the record position? I cannot understand,
> can you give a simple example?
>
>
> On Wed, Mar 13, 2013 at 9:56 AM, Roth Effy <effyroth@gmail.com> wrote:
>
>> sorry´╝îI still can't understand how to use recordreader in the
>> reduce(),because the input is a RawKeyValueIterator in the class
>> reducecontext.so,I'm confused.
>> anyway,thank you.
>>
>>
>> 2013/3/12 samir das mohapatra <samir.helpdoc@gmail.com>
>>
>>> Through the RecordReader and FileStatus you can get it.
>>>
>>>
>>> On Tue, Mar 12, 2013 at 4:08 PM, Roth Effy <effyroth@gmail.com> wrote:
>>>
>>>> Hi,everyone,
>>>> I want to join the k-v pairs in Reduce(),but how to get the record
>>>> position?
>>>> Now,what I thought is to save the context status,but class Context
>>>> doesn't implement a clone construct method.
>>>>
>>>> Any help will be appreciated.
>>>> Thank you very much.
>>>>
>>>
>>>
>>
>

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