incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Pierre-Yves Ritschard <...@spootnik.org>
Subject Re: CQL3 Compound Primary Keys - Do I have the right idea?
Date Sun, 23 Dec 2012 01:00:02 GMT
Is there still a way to have composite row keys ?
There are times when you want to partition wide rows by a tuple instead of
pushing the composites into column names.

Lists could do the trick but would not allow multiple types and aren't
allowed as primary keys anyhow.

At some point I remember seeing a "token" syntax, is that still supposed to
make it to 1.2 ?





On Sat, Dec 22, 2012 at 1:38 PM, Brian O'Neill <bone@alumni.brown.edu>wrote:

>
> Agreed.  I actually flip between cli and cqlsh these days.
>
> cqlsh shows the logical view.
> cli shows the physical view.
>
> This is useful, especially when developing using a thrift-based client.
> Here are the slides<http://mkto-q0127.com/track?type=click&enid=bWFpbGluZ2lkPWRhdGFzdGF4QmV0YWN1c3QtMTI4MC0xOTkxLTAtMTIwNS1wcm9kLTIwOSZtZXNzYWdlaWQ9MCZkYXRhYmFzZWlkPTIwOSZzZXJpYWw9MTMwMDAwNzk1MCZlbWFpbGlkPWJvbmVAYWx1bW5pLmJyb3duLmVkdSZ1c2VyaWQ9MTA1NTc2MS0xJmV4dHJhPSYmJg==&&&http://www.slideshare.net/DataStax/college-credit-creating-your-first-app-in-java-with-cassandra?mkt_tok=3RkMMJWWfF9wsRonuaTJZKXonjHpfsX56%2BkoXqG3lMI%2F0ER3fOvrPUfGjI4ATsJnI%2FqLAzICFpZo2FFcG%2FSUb5RB4g%3D%3D>
>  and video<http://mkto-q0127.com/track?type=click&enid=bWFpbGluZ2lkPWRhdGFzdGF4QmV0YWN1c3QtMTI4MC0xOTkxLTAtMTIwNS1wcm9kLTIwOSZtZXNzYWdlaWQ9MCZkYXRhYmFzZWlkPTIwOSZzZXJpYWw9MTMwMDAwNzk1MCZlbWFpbGlkPWJvbmVAYWx1bW5pLmJyb3duLmVkdSZ1c2VyaWQ9MTA1NTc2MS0xJmV4dHJhPSYmJg==&&&http://youtu.be/AdfugJxfd0o?mkt_tok=3RkMMJWWfF9wsRonuaTJZKXonjHpfsX56%2BkoXqG3lMI%2F0ER3fOvrPUfGjI4ATsJnI%2FqLAzICFpZo2FFcG%2FSUb5RB4g%3D%3D>
if
> you want to have a look.
>
> -brian
>
>
>
> On Dec 22, 2012, at 3:36 AM, Wz1975 wrote:
>
> You still add one row. The  column name is the remaining part of the
> composite key (repeat for each column) plus each of the column which is not
> in the composite key. I found it is much clearer to look at the data
> through Cassandra -cli which shows you how data is stored.
>
>
> Thanks.
> -Wei
>
> Sent from my Samsung smartphone on AT&T
>
>
> -------- Original message --------
> Subject: CQL3 Compound Primary Keys - Do I have the right idea?
> From: Adam Venturella <aventurella@gmail.com>
> To: user@cassandra.apache.org
> CC:
>
>
> Trying to better grasp compound primary keys and what they are
> conceptually doing under the hood. When you create a table with a compound
> primary key in cql3 (
> http://www.datastax.com/dev/blog/schema-in-cassandra-1-1) the first part
> of the key is the partition key. I get that and the subsequent parts help
> with the row name as I understand it.
>
> So when you add a new row to that columnfamily/table, you are still adding
> a row. In other words, the RandomPartitioner places it somewhere in the
> cluster as a row on it's own as opposed to just adding a new column to an
> existing row, which would live on the same node as the row
>
> The effect of the compound key means that those rows are effectively
> treated as if they were part of the same column, making it a wide column.
>
> Is that the right idea or do I have the row / rp thing wrong?
>
>
>
> Brian ONeill
> Lead Architect, Health Market Science (http://healthmarketscience.com)
> mobile:215.588.6024
> blog: http://weblogs.java.net/blog/boneill42/
> blog: http://brianoneill.blogspot.com/
>
>

Mime
View raw message