I think there are several issues in your schema and queries.
First, the schema can't efficiently return the single newest post for every
author. It can efficiently return the newest N posts for a particular
author.
On Fri, May 16, 2014 at 11:53 PM, 後藤 泰陽 wrote:
>
> But I consider LIMIT to be a
Hmm. Something like a user-managed-index looks the only way to do what I
want to do.
Thank you, I'll try that.
2014-05-17 18:07 GMT+09:00 DuyHai Doan :
> Clearly with your current data model, having X latest post for each author
> is not possible.
>
> However, what's about this ?
>
> CREATE TAB
Clearly with your current data model, having X latest post for each author
is not possible.
However, what's about this ?
CREATE TABLE latest_posts_per_user (
author ascii
latest_post map,
PRIMARY KEY (author)
)
The latest_post will keep a collection of X latest posts for each user.
No
Hello,
Thank you for your addressing.
But I consider LIMIT to be a keyword to limits result numbers from WHOLE
results retrieved by the SELECT statement.
The result with SELECT.. LIMIT is below. Unfortunately, This is not what I
wanted.
I wante latest posts of each authors. (Now I doubt if CQL3
Hi, I'm modeling some queries in CQL3.
I'd like to query first 1 columns for each partitioning keys in CQL3.
For example:
create table posts(
> author ascii,
> created_at timeuuid,
> entry text,
> primary key(author,created_at)
> );
> insert into posts(author,created_at,entry) values
> ('john',m
Hello,
Have you looked at using the CLUSTERING ORDER BY and LIMIT features of
CQL3?
These may help you achieve your goals.
http://www.datastax.com/documentation/cql/3.1/cql/cql_reference/refClstrOrdr.html
http://www.datastax.com/documentation/cql/3.1/cql/cql_reference/select_r.html
Jonathan
