cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Cristian Opris (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-4989) Expose new SliceQueryFilter features through Thrift interface
Date Mon, 25 Mar 2013 11:19:15 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-4989?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13612553#comment-13612553
] 

Cristian Opris commented on CASSANDRA-4989:
-------------------------------------------

Yes, Sylvain is correct. This is essentially an optimization to avoid "iterating" through
the columns and just get the latest group that has a common prefix. I noticed this can be
done with the new SliceQueryFilter so it would be useful if it can be exposed.

If I'm allowed to go off on a tangent here (I know, not the best place) having more pluggable
behaviour would be an interesting direction to take with Cassandra. Same way it's possible
to have custom column comparators, maybe we could have pluggable row level indexes, pluggable
queries to use them, pluggable notification systems, etc. I know this has been discussed before,
just wanted to add my vote here.

Thanks
                
> Expose new SliceQueryFilter features through Thrift interface
> -------------------------------------------------------------
>
>                 Key: CASSANDRA-4989
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-4989
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: API
>    Affects Versions: 1.2.0, 1.2.1, 2.0
>            Reporter: Cristian Opris
>
> SliceQueryFilter has some very useful new features like ability to specify a composite
column prefix to group by and specify a limit of groups to return.
> This is very useful if for example I have a wide row with columns prefixed by timestamp
and I want to retrieve the latest columns, but I don't know the column names. Say I have a
row
> {{row -> (t1, c1), (t1, c2)... (t1, cn) ... (t0,c1) ... etc}}
> Query slice range (t1,) group by prefix (1) limit (1)
> As a more general question, is the Thrift interface going to be kept up-to-date with
the feature changes or will it be left behind (a mistake IMO) ?

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message