Join between replicated and partitioned caches

[Clay Teahouse <cl...@gmail.com>]

Hello All,

I am using SqlFieldsQuery to execute sql queries and I am setting the
option setLocal to true to process the local data only. What happens if the
sql has a join with a replicated cache?

thank you
Clay

Re: Join between replicated and partitioned caches

[akorensh <al...@gmail.com>]

Hi,

What matters is how the data is finally distributed after all affinity keys
(or lack thereof)are taken into account.

If you are joining using an affinity key column then it is called a
collocated join as each set of data can be fully retrieved from a single
node, then added together.
If you are not joining using an affinity key, then it is a non-collocated
join and Ignite will need to locate data housed on different nodes during
the join process.

Details are fully explained here:
https://ignite.apache.org/docs/latest/SQL/distributed-joins

Thanks, Alex



--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/

Re: Join between replicated and partitioned caches

[Clay Teahouse <cl...@gmail.com>]

Thanks. How about a join between two partitioned tables with different
affinity keys or a join between two tables with one having an affinity key
defined and the other with no affinity key explicitly defined?

On Tue, Jan 19, 2021 at 11:59 AM Craig Gresbrink <CG...@24hourfit.com>
wrote:

> Since a replicated cache has an entire copy of all its data on each server
> node, the data is local so you can join to it is my understanding.
>
>
>
> *From:* Clay Teahouse <cl...@gmail.com>
> *Sent:* Tuesday, January 19, 2021 9:49 AM
> *To:* user@ignite.apache.org
> *Subject:* Join between replicated and partitioned caches
>
>
>
> *CAUTION:* This email originated outside 24 Hour Fitness. Do not click
> links or open attachments unless you recognize the sender and know the
> content is safe.
>
>
>
> Hello All,
>
>
>
> I am using SqlFieldsQuery to execute sql queries and I am setting the
> option setLocal to true to process the local data only. What happens if the
> sql has a join with a replicated cache?
>
>
>
> thank you
>
> Clay
>

RE: Join between replicated and partitioned caches

[Craig Gresbrink <CG...@24HourFit.com>]

Since a replicated cache has an entire copy of all its data on each server node, the data is local so you can join to it is my understanding.

From: Clay Teahouse <cl...@gmail.com>
Sent: Tuesday, January 19, 2021 9:49 AM
To: user@ignite.apache.org
Subject: Join between replicated and partitioned caches

CAUTION: This email originated outside 24 Hour Fitness. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Hello All,

I am using SqlFieldsQuery to execute sql queries and I am setting the option setLocal to true to process the local data only. What happens if the sql has a join with a replicated cache?

thank you
Clay