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Date: Sat, 04 May 2013 14:30:36 -0400
From: Dave Brosius <dbrosius@mebigfatguy.com>
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To: user@cassandra.apache.org
Subject: Re: Look table structuring advice
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if you want to store all the roles in one row, you can do

create table roles (synthetic_key int, name text, primary 
key(synthetic_key, name)) with compact storage

when inserting roles, just use the same key

insert into roles (synthetic_key, name) values (0, 'Programmer');
insert into roles (synthetic_key, name) values (0, 'Tester');

and use

select * from roles where synthetic_key = 0;


(or some arbitrary key value you decide to use)

the that data is stored on one node (and its replicas)

of course if the number of roles grows to be large, you lose most of the 
value in having a cluster.


On 05/04/2013 12:09 PM, Jabbar Azam wrote:
> Hello,
>
> I want to create a simple table holding user roles e.g.
>
> create table roles (
>        name text,
>        primary key(name)
> );
>
> If I want to get a list of roles for some admin tool I can use the 
> following CQL3
>
> select * from roles;
>
> When a new name is added it will be stored on a different host and 
> doing a select * is going to be inefficient because the table will be 
> stored across the cluster and each node will respond. The number of 
> roles may be less than or just greater than a dozen. I'm not sure if 
> I'm storing the roles correctly.
>
>
> The other thing I'm thinking about is that when I've read the roles 
> once then I can cache them.
>
> Thanks
>
> Jabbar Azam