Re: [Postgres-xc-developers] Data distribution by hash - general question

[Adam D. <ada...@gm...>]

Yes A is like a parent and all the others are like a children (joined with
foreign key)...so using parent primary key (id) I will be sure that the
data (that are joined) will all stay at the same node? What about the
situation when table B is also joined (using foreign key) with some other
table? Is that the same?


2013/7/16 Mason Sharp <ma...@st...>

> Adam,
>
> Is "id" present in all of A,B,C, and D? Is A the parent and the other
> children and used as a foreign key from B,C, and D to A? If so, yes, on the
> surface it sounds like you can do that and be able to take advantage of
> pushing down joins to the local data nodes.
>
> Regards,
>
> Mason
>
>
> On Mon, Jul 15, 2013 at 9:03 AM, Adam Dec <ada...@gm...> wrote:
>
>> Hi!
>>
>> My topology: 2 machines (on each machine 1 master coordinator and 1
>> master datannode)
>>
>> Lets say that I have a table A which has
>> - one-to-many relation with table B
>> - one-to-many relation to table C
>> - one-to-one relation with table D
>>
>> I would like to distribute it in the cluster. All I have to do is to put
>> DISTRIBUTE BY HASH(id); in each of the tables while creating them?
>> id - primary key
>>
>> In my example Table A is like a root of the graph. How to create such a
>> "graph of tables" to be shure
>> that when I will invoke a select with joins all the proceesin will be
>> done only on the one node.
>> I do not want to replicate all the data.
>>
>> Where can I read about data distribution in Postgres XC? Do you have any
>> examples that I could look at?
>>
>>
>> Regards,
>>
>> Adam Dec
>>
>>
>> ------------------------------------------------------------------------------
>> See everything from the browser to the database with AppDynamics
>> Get end-to-end visibility with application monitoring from AppDynamics
>> Isolate bottlenecks and diagnose root cause in seconds.
>> Start your free trial of AppDynamics Pro today!
>>
>> http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk
>> _______________________________________________
>> Postgres-xc-developers mailing list
>> Pos...@li...
>> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>>
>>
>
>
> --
> Mason Sharp
>
> StormDB - http://www.stormdb.com
> The Database Cloud
> Postgres-XC Support and Services
>