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Posted to user@hive.apache.org by Cam Bazz <ca...@gmail.com> on 2012/06/13 18:46:18 UTC
joining user sessions
hello,
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,
Re: joining user sessions
Posted by Bejoy KS <be...@yahoo.com>.
Yes, the framework takes care of this.
Regards
Bejoy KS
Sent from handheld, please excuse typos.
-----Original Message-----
From: Cam Bazz <ca...@gmail.com>
Date: Wed, 13 Jun 2012 20:09:12
To: <us...@hive.apache.org>; <be...@yahoo.com>
Reply-To: user@hive.apache.org
Subject: Re: joining user sessions
Thank you. But how do I put the smaller table into distributed cache?
is it done magically when we do a hive.auto.convert.join=true ?
On Wed, Jun 13, 2012 at 7:52 PM, Bejoy KS <be...@yahoo.com> wrote:
> Hi,
>
> 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;
> Regards
> Bejoy KS
>
> Sent from handheld, please excuse typos.
>
> -----Original Message-----
> From: Cam Bazz <ca...@gmail.com>
> Date: Wed, 13 Jun 2012 19:46:18
> To: <us...@hive.apache.org>
> Reply-To: user@hive.apache.org
> Subject: joining user sessions
>
> hello,
>
> 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,
Re: joining user sessions
Posted by Cam Bazz <ca...@gmail.com>.
Thank you. But how do I put the smaller table into distributed cache?
is it done magically when we do a hive.auto.convert.join=true ?
On Wed, Jun 13, 2012 at 7:52 PM, Bejoy KS <be...@yahoo.com> wrote:
> Hi,
>
> 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;
> Regards
> Bejoy KS
>
> Sent from handheld, please excuse typos.
>
> -----Original Message-----
> From: Cam Bazz <ca...@gmail.com>
> Date: Wed, 13 Jun 2012 19:46:18
> To: <us...@hive.apache.org>
> Reply-To: user@hive.apache.org
> Subject: joining user sessions
>
> hello,
>
> 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,
Re: joining user sessions
Posted by Bejoy KS <be...@yahoo.com>.
Hi,
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;
Regards
Bejoy KS
Sent from handheld, please excuse typos.
-----Original Message-----
From: Cam Bazz <ca...@gmail.com>
Date: Wed, 13 Jun 2012 19:46:18
To: <us...@hive.apache.org>
Reply-To: user@hive.apache.org
Subject: joining user sessions
hello,
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,