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Hive >> mail # user >> joining user sessions

Cam Bazz 2012-06-13, 16:46
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Re: joining user sessions

If one of your tables are small enough then you can go in for map side joins, which actually distributes the smaller table contents into the distributed cache and then perform the join which is much faster compared to normal reduce side joins.

To enable map side joins, before executing join query set the following property
hive> hive.auto.convert.join=true;
Bejoy KS

Sent from handheld, please excuse typos.

-----Original Message-----
From: Cam Bazz <[EMAIL PROTECTED]>
Date: Wed, 13 Jun 2012 19:46:18
Subject: joining user sessions


for all the log files i have i log the session id and user cookie. now
i need to seperate certain items of certain users, so i need to join
all my data to a global cookike table.

what are some common practices doing this? just put it in a table and
join? or maybe keep them in some sort of in memory cache?

and ideas / recomendations greatly appreciated.

best regards,
Cam Bazz 2012-06-13, 17:09
Bejoy KS 2012-06-13, 17:10