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From Jun Young Kim <juneng...@gmail.com>
Subject Re: is it possible to map an one from a a file and an one from cassandra?
Date Mon, 17 Jan 2011 02:14:32 GMT
thanks for all.

-----
Junyoung Kim (juneng603@gmail.com)

On 01/17/2011 10:58 AM, Aaron Morton wrote:
> Thanks for the update.
> Aaron
>
>
> On 17 Jan, 2011,at 02:51 PM, Brandon Williams <driftx@gmail.com> wrote:
>
>> 2011/1/16 Jun Young Kim <juneng603@gmail.com 
>> <mailto:juneng603@gmail.com>>
>>
>>     Hi aron.
>>
>>     I think that if the pig is able to support to map it, the same
>>     job could be represented in java code itself.
>>
>>     I believe that we can call a map function by loading a file and
>>     cassandra at the same time.
>>
>>     Ps) I dont need to join from them. I just wanna compare each keys
>>     which are read from them.
>>
>>
>> We went over this on irc, but I will repeat the summary for posterity.
>>
>> This is a case where using the thrift API, rather than a o.a.c.hadoop 
>> construct is probably better (right now) because 
>> ColumnFamilyInputFormat expects to go over the entire CF, and a join 
>> the reducer is costly.  Instead what you really want is per-row 
>> access after reading an entry from the file in the map task, so using 
>> Hector inside the hadoop job makes the most sense.
>>
>> -Brandon

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