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From abhiTowson cal <abhishek.dod...@gmail.com>
Subject Re: STREAM (TABLE) IN HIVE
Date Thu, 26 Jul 2012 20:01:34 GMT
Thank you Bejoy.

Regards
Abhishek

On Thu, Jul 26, 2012 at 3:57 PM, Bejoy Ks <bejoy_ks@yahoo.com> wrote:
> Hi Abshiek
>
> From my understanding, when you have the join happening in map or reduce,
> the values corresponding to a key from all all table's except one (if two
> tables are involved in join on same key, then just one table here) are
> buffered in memory and the left out one is streamed. Usually it is the
> largest table to be streamed, else the larger data can go into the
> memory(buffer) and create OOM errors.
>
> This stream table hint is used to specify which table to be streamed. By
> default it is the table that comes on the right is streamed and the other is
> buffered. But if you wan't  other  than right table to be streamed you go
> for this hint.
>
> If you are joining more tables on different keys, then for every join set
> just specify the larger table on the right of ON condition. No need of
> stream table hint here.
>
>
> Regards
> Bejoy KS
>
> ________________________________
> From: abhiTowson cal <abhishek.dodda1@gmail.com>
> To: user@hive.apache.org
> Sent: Friday, July 27, 2012 12:50 AM
> Subject: STREAM (TABLE) IN HIVE
>
> HI all,
>
> Can any one explain me how stream table in hive works
> What is the importance of STREAM TABLE?
> When should i use it?
> Suppose i am joining four to five tables
> Which table should be mentioned in the STREAM table hint?
> Should Big Table be specified in the STREAM TABLE hint or Small Table
>
> Regards
> Abhishek
>
>

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